diff --git a/.DS_Store b/.DS_Store
index e82ca7ed..1bea640e 100644
Binary files a/.DS_Store and b/.DS_Store differ
diff --git a/src/.DS_Store b/src/.DS_Store
index 83a4c15f..97314535 100644
Binary files a/src/.DS_Store and b/src/.DS_Store differ
diff --git a/src/main/.DS_Store b/src/main/.DS_Store
index a068fe57..b3d027d0 100644
Binary files a/src/main/.DS_Store and b/src/main/.DS_Store differ
diff --git a/src/main/java/.DS_Store b/src/main/java/.DS_Store
index 419e452f..ef52379d 100644
Binary files a/src/main/java/.DS_Store and b/src/main/java/.DS_Store differ
diff --git a/src/main/java/org/.DS_Store b/src/main/java/org/.DS_Store
index e6675bd3..fcb8f060 100644
Binary files a/src/main/java/org/.DS_Store and b/src/main/java/org/.DS_Store differ
diff --git a/src/main/java/org/ezcode/codetest/application/usermanagement/user/service/UserService.java b/src/main/java/org/ezcode/codetest/application/usermanagement/user/service/UserService.java
index 6a41b981..bf4ea115 100644
--- a/src/main/java/org/ezcode/codetest/application/usermanagement/user/service/UserService.java
+++ b/src/main/java/org/ezcode/codetest/application/usermanagement/user/service/UserService.java
@@ -1,5 +1,6 @@
 package org.ezcode.codetest.application.usermanagement.user.service;
 
+import java.time.LocalDate;
 import java.time.LocalDateTime;
 import java.time.temporal.ChronoUnit;
 import java.util.List;
@@ -56,7 +57,7 @@ public class UserService {
 	private final RedisTemplate<String, String> redisTemplate;
 	private final S3Uploader s3Uploader;
 
-	@Transactional(readOnly = true)
+	@Transactional
 	public UserInfoResponse getUserInfo(AuthUser authUser) {
 		log.info("authUserEmail: {}, authUserID : {}", authUser.getEmail(), authUser.getId());
 		User user = userDomainService.getUserById(authUser.getId());
@@ -64,6 +65,10 @@ public UserInfoResponse getUserInfo(AuthUser authUser) {
 		List<UserAuthType> userAuthTypes = userDomainService.getUserAuthTypesByUser(user);
 		List<AuthType> authTypes = userAuthTypes.stream()
 			.map(UserAuthType::getAuthType).toList();
+		if (user.getLanguage() == null) {
+			Language userLanguage = languageDomainService.getLanguage(1L);
+			user.setLanguage(userLanguage);
+		}
 
 		return UserInfoResponse.builder()
 			.username(user.getUsername())
@@ -87,6 +92,12 @@ public UserInfoResponse getUserInfo(AuthUser authUser) {
 	public UserInfoResponse modifyUserInfo(AuthUser authUser, ModifyUserInfoRequest request, MultipartFile image) {
 		User user = userDomainService.getUserById(authUser.getId());
 		Language findLangauge = languageDomainService.getLanguage(request.languageId());
+		if (request.nickname() != null && !request.nickname().equals(user.getNickname())) {
+			if (userDomainService.existsByNickname(request.nickname())) {
+				log.info("중복 닉네임");
+				throw new UserException(UserExceptionCode.ALREADY_EXIST_NICKNAME);
+			}
+		}
 
 		user.modifyUserInfo(
 			request.nickname(),
diff --git a/src/main/java/org/ezcode/codetest/domain/submission/dto/DailyCorrectCount.java b/src/main/java/org/ezcode/codetest/domain/submission/dto/DailyCorrectCount.java
index 957c3c7c..b30b8651 100644
--- a/src/main/java/org/ezcode/codetest/domain/submission/dto/DailyCorrectCount.java
+++ b/src/main/java/org/ezcode/codetest/domain/submission/dto/DailyCorrectCount.java
@@ -1,12 +1,10 @@
 package org.ezcode.codetest.domain.submission.dto;
 
 import java.time.LocalDate;
+import java.util.Set;
 
 public record DailyCorrectCount(
     LocalDate date,
-    int count
-) {
-    public DailyCorrectCount(java.sql.Date date, int count) {
-        this(date.toLocalDate(), count);
-    }
-}
+    Long count,
+    Set<Long> problemIds
+) {  }
diff --git a/src/main/java/org/ezcode/codetest/domain/submission/service/SubmissionDomainService.java b/src/main/java/org/ezcode/codetest/domain/submission/service/SubmissionDomainService.java
index 76069406..a41cfc38 100644
--- a/src/main/java/org/ezcode/codetest/domain/submission/service/SubmissionDomainService.java
+++ b/src/main/java/org/ezcode/codetest/domain/submission/service/SubmissionDomainService.java
@@ -1,5 +1,6 @@
 package org.ezcode.codetest.domain.submission.service;
 
+import java.time.LocalDate;
 import java.time.LocalDateTime;
 import java.util.List;
 import java.util.Optional;
@@ -120,4 +121,5 @@ private void modifyUserProblemResult(UserProblemResult userProblemResult, boolea
     public int findSubmissionCountByUserId(Long userId) {
         return submissionRepository.findSubmissionCountByUserId(userId);
     }
+
 }
diff --git a/src/main/java/org/ezcode/codetest/domain/user/exception/code/UserExceptionCode.java b/src/main/java/org/ezcode/codetest/domain/user/exception/code/UserExceptionCode.java
index d9638efb..fc2825e5 100644
--- a/src/main/java/org/ezcode/codetest/domain/user/exception/code/UserExceptionCode.java
+++ b/src/main/java/org/ezcode/codetest/domain/user/exception/code/UserExceptionCode.java
@@ -15,8 +15,7 @@ public enum UserExceptionCode implements ResponseCode {
 	NO_GITHUB_INFO(false, HttpStatus.BAD_REQUEST, "깃허브 정보가 없습니다."),
 	NO_GITHUB_REPO(false, HttpStatus.BAD_REQUEST, "해당하는 Repository를 찾을 수 없습니다."),
 
-
-	;
+    ALREADY_EXIST_NICKNAME(false, HttpStatus.BAD_REQUEST, "이미 존재하는 닉네임입니다");
 	private final boolean success;
 	private final HttpStatus status;
 	private final String message;
diff --git a/src/main/java/org/ezcode/codetest/domain/user/model/entity/User.java b/src/main/java/org/ezcode/codetest/domain/user/model/entity/User.java
index 34757119..f09709e1 100644
--- a/src/main/java/org/ezcode/codetest/domain/user/model/entity/User.java
+++ b/src/main/java/org/ezcode/codetest/domain/user/model/entity/User.java
@@ -216,4 +216,8 @@ public void modifyProfileImage(String profileImageUrl) {
 	public void modifyUserRole(UserRole userRole) {
 		this.role = userRole;
 	}
+
+	public void setLanguage(Language userLanguage) {
+		this.language = userLanguage;
+	}
 }
diff --git a/src/main/java/org/ezcode/codetest/domain/user/repository/UserRepository.java b/src/main/java/org/ezcode/codetest/domain/user/repository/UserRepository.java
index 9eea7b4d..6a2079bc 100644
--- a/src/main/java/org/ezcode/codetest/domain/user/repository/UserRepository.java
+++ b/src/main/java/org/ezcode/codetest/domain/user/repository/UserRepository.java
@@ -22,4 +22,5 @@ public interface UserRepository {
 
 	void updateUserGithubAccessToken(User loginUser);
 
+	List<String> getUserNicknames();
 }
diff --git a/src/main/java/org/ezcode/codetest/domain/user/service/UserDomainService.java b/src/main/java/org/ezcode/codetest/domain/user/service/UserDomainService.java
index d3fcf3d4..e01ce696 100644
--- a/src/main/java/org/ezcode/codetest/domain/user/service/UserDomainService.java
+++ b/src/main/java/org/ezcode/codetest/domain/user/service/UserDomainService.java
@@ -132,4 +132,11 @@ public List<UserAuthType> getUserAuthTypesByUser(User user) {
 		return userAuthTypeRepository.getUserAuthTypesByUser(user);
 	}
 
+    public List<String> getUserNicknames() {
+		return userRepository.getUserNicknames();
+    }
+
+    public boolean existsByNickname(String nickname) {
+		return userRepository.existsByNickname(nickname);
+    }
 }
diff --git a/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/submission/query/UserProblemResultQueryRepositoryImpl.java b/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/submission/query/UserProblemResultQueryRepositoryImpl.java
index 195c6f26..2bc42544 100644
--- a/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/submission/query/UserProblemResultQueryRepositoryImpl.java
+++ b/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/submission/query/UserProblemResultQueryRepositoryImpl.java
@@ -1,13 +1,17 @@
 package org.ezcode.codetest.infrastructure.persistence.repository.submission.query;
 
 
+import java.time.LocalDate;
 import java.util.List;
+import java.util.Set;
 
 import org.ezcode.codetest.domain.submission.dto.DailyCorrectCount;
 import org.ezcode.codetest.domain.submission.model.entity.QUserProblemResult;
 import org.springframework.stereotype.Repository;
 
+import com.querydsl.core.group.GroupBy;
 import com.querydsl.core.types.Projections;
+import com.querydsl.core.types.dsl.NumberExpression;
 import com.querydsl.core.types.dsl.Expressions;
 import com.querydsl.jpa.impl.JPAQueryFactory;
 
@@ -24,20 +28,25 @@ public List<DailyCorrectCount> countCorrectByUserGroupedByDate(Long userId) {
 
         QUserProblemResult upr = QUserProblemResult.userProblemResult;
 
-        var date = Expressions.dateTemplate(java.sql.Date.class, "DATE({0})", upr.modifiedAt);
+        var date = Expressions.dateTemplate(LocalDate.class, "DATE({0})", upr.modifiedAt);
+        NumberExpression<Long> countDistinctProblem = upr.problem.id.countDistinct();
 
         return queryFactory
-            .select(Projections.constructor(DailyCorrectCount.class,
-                date,
-                upr.count().intValue()
-            ))
             .from(upr)
             .where(
                 upr.user.id.eq(userId),
                 upr.isCorrect.eq(true)
             )
-            .groupBy(date)
             .orderBy(date.asc())
-            .fetch();
+            .transform(
+                GroupBy.groupBy(date).list(
+                    Projections.constructor(
+                        DailyCorrectCount.class,
+                        date,
+                        countDistinctProblem,
+                        GroupBy.set(upr.problem.id)
+                    )
+                )
+            );
     }
 }
diff --git a/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/user/UserJpaRepository.java b/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/user/UserJpaRepository.java
index a7e559c2..533e92e9 100644
--- a/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/user/UserJpaRepository.java
+++ b/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/user/UserJpaRepository.java
@@ -24,4 +24,7 @@ void updateReviewTokens(
 		@Param("ids") List<Long> ids,
 		@Param("newToken") int newToken
 	);
+
+	@Query("select u.nickname from User u ")
+	List<String> findAllNicknames();
 }
diff --git a/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/user/UserRepositoryImpl.java b/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/user/UserRepositoryImpl.java
index a9090b38..765cd5b6 100644
--- a/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/user/UserRepositoryImpl.java
+++ b/src/main/java/org/ezcode/codetest/infrastructure/persistence/repository/user/UserRepositoryImpl.java
@@ -53,6 +53,9 @@ public void updateUserGithubAccessToken(User loginUser) {
 		userJpaRepository.save(loginUser);
 	}
 
-
+	@Override
+	public List<String> getUserNicknames() {
+		return userJpaRepository.findAllNicknames();
+	}
 
 }
diff --git a/src/main/java/org/ezcode/codetest/presentation/usermanagement/UserController.java b/src/main/java/org/ezcode/codetest/presentation/usermanagement/UserController.java
index 9dc7e60b..27f2c0f4 100644
--- a/src/main/java/org/ezcode/codetest/presentation/usermanagement/UserController.java
+++ b/src/main/java/org/ezcode/codetest/presentation/usermanagement/UserController.java
@@ -13,6 +13,7 @@
 import org.ezcode.codetest.application.usermanagement.user.service.UserService;
 import org.ezcode.codetest.domain.user.model.entity.AuthUser;
 import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.security.core.annotation.AuthenticationPrincipal;
 import org.springframework.web.bind.annotation.DeleteMapping;
@@ -46,7 +47,7 @@ public ResponseEntity<UserInfoResponse> getUserInfo(@AuthenticationPrincipal Aut
 	}
 
 	@Operation(summary = "내 정보 수정", description = "닉네임, 블로그, 깃허브, 소개 등 개인 정보를 추가하거나 수정합니다.")
-    @PutMapping("/users")
+    @PutMapping(value = "/users", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
 	public ResponseEntity<UserInfoResponse> modifyUserInfo(
 		@AuthenticationPrincipal AuthUser authUser,
 		@Valid @RequestPart("request") ModifyUserInfoRequest request,
@@ -90,6 +91,7 @@ public ResponseEntity<UserReviewTokenResponse> getReviewToken(
 		return ResponseEntity.status(HttpStatus.OK).body(userService.getReviewToken(authUser));
 	}
 
+	@Operation(summary = "회원의 푼 문제 수 조회", description = "날짜, 날짜마다 푼 문제 번호 리스트, 푼 문제 개수")
 	@GetMapping("/users/daily-solved")
 	public ResponseEntity<UserDailySolvedHistoryResponse> getUserDailySolvedHistory(
 		@AuthenticationPrincipal AuthUser authUser
diff --git a/src/main/java/org/ezcode/codetest/presentation/usermanagement/UserVerifyController.java b/src/main/java/org/ezcode/codetest/presentation/usermanagement/UserVerifyController.java
index 7b2b640a..89e94a09 100644
--- a/src/main/java/org/ezcode/codetest/presentation/usermanagement/UserVerifyController.java
+++ b/src/main/java/org/ezcode/codetest/presentation/usermanagement/UserVerifyController.java
@@ -1,5 +1,7 @@
 package org.ezcode.codetest.presentation.usermanagement;
 
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.HttpHeaders;
 import org.ezcode.codetest.application.usermanagement.auth.dto.request.FindPasswordRequest;
 import org.ezcode.codetest.application.usermanagement.user.dto.request.ResetPasswordRequest;
 import org.ezcode.codetest.application.usermanagement.auth.dto.request.SendEmailRequest;
diff --git a/src/main/resources/application.properties b/src/main/resources/application.properties
index bf1c9786..3ac0c698 100644
--- a/src/main/resources/application.properties
+++ b/src/main/resources/application.properties
@@ -159,4 +159,12 @@ spring.datasource.hikari.minimum-idle=10
 spring.datasource.hikari.idle-timeout=30000
 spring.datasource.hikari.max-lifetime=600000
 spring.datasource.hikari.connection-timeout=30000
-spring.datasource.hikari.validation-timeout=5000
\ No newline at end of file
+spring.datasource.hikari.validation-timeout=5000
+
+# ========================
+# App Redirects (Email Verify)
+# ========================
+# 인증 성공 시 이동할 페이지 URL (예: 프론트의 성공 안내 페이지)
+app.redirect.verify.success=${APP_REDIRECT_VERIFY_SUCCESS:https://your-frontend.example.com/verify/success}
+# 인증 실패 시 이동할 페이지 URL (예: 프론트의 실패 안내 페이지)
+app.redirect.verify.failure=${APP_REDIRECT_VERIFY_FAILURE:https://your-frontend.example.com/verify/failure}
\ No newline at end of file