diff --git a/src/PollinationSDK/Client/Configuration.cs b/src/PollinationSDK/Client/Configuration.cs
index 4fd57eac..28820d1b 100644
--- a/src/PollinationSDK/Client/Configuration.cs
+++ b/src/PollinationSDK/Client/Configuration.cs
@@ -301,11 +301,7 @@ public virtual string AccessToken
         {
             get
             {
-                if (TokenRepo != null)
-                {
-                    return TokenRepo.GetToken();
-                }
-                return "";
+                return TokenRepo?.GetToken();
             }
         }
 
diff --git a/src/PollinationSDK/Helper/AuthHelper.cs b/src/PollinationSDK/Helper/AuthHelper.cs
index 8e9540fa..68fd6c3a 100644
--- a/src/PollinationSDK/Helper/AuthHelper.cs
+++ b/src/PollinationSDK/Helper/AuthHelper.cs
@@ -199,6 +199,7 @@ private static bool CheckGetUser(AuthResult auth, out string errorMessage, bool
                     refreshURL: devEnv ? RefreshURL_Dev : RefreshURL,
                     idToken: auth.IDToken,
                     expiresInSeconds: auth.ExpiresInSeconds,
+                    //expiresInSeconds: 62, // for testing. expires in 1 minute, but it should be refreshed in 2 seconds.
                     refreshToken: auth.RefreshToken
                 );
                 Helper.CurrentUser = Helper.GetUser();
diff --git a/src/PollinationSDK/Helper/Helper.cs b/src/PollinationSDK/Helper/Helper.cs
index 680ce50d..879b4bc0 100644
--- a/src/PollinationSDK/Helper/Helper.cs
+++ b/src/PollinationSDK/Helper/Helper.cs
@@ -95,17 +95,49 @@ public static async Task<bool> UploadDirectoryAsync(Project project, string dire
 
             var files = Directory.GetFiles(directory, "*", SearchOption.AllDirectories);
             var api = new ArtifactsApi();
-            
 
-            var tasks = files.Select(_ => UploadArtifactAsync(api, project, _, _.Replace(directory, ""))).ToList();
             var total = files.Count();
-
             LogHelper.LogInfo($"Uploading {total} assets for project {project.Name}");
 
-
+            var finished = 0;
             var finishedPercent = 0;
             reportProgressAction?.Invoke(finishedPercent);
 
+            var chunkSize = 20;
+            var subLists = files.Select((x, i) => new { Index = i, Value = x })
+            .GroupBy(x => x.Index / chunkSize)
+            .Select(x => x.Select(v => v.Value).ToList())
+            .ToList();
+
+            Action<int> reportPercent = (c) =>
+            {
+                var p = finished + c;
+                finishedPercent = (int)(p * 100 / total);
+                reportProgressAction?.Invoke(finishedPercent);
+            };
+
+            foreach (var chunk in subLists)
+            {
+                var chunkFiles = chunk.Select(_ => (_, _.Replace(directory, ""))).ToList();
+                await BatchExecute(api, project, chunkFiles, reportPercent, cancellationToken);
+                // auto refresh token between each chunk run
+                api.Configuration.TokenRepo?.CheckToken();
+                finished += chunk.Count;
+            }
+
+            LogHelper.LogInfo($"Finished uploading assets for project {project.Name}");
+
+            // canceled by user
+            if (cancellationToken.IsCancellationRequested) return false;
+
+            return true;
+        }
+        
+        private static async Task<bool> BatchExecute(ArtifactsApi api, Project project, List<(string path, string relativePath)> files , Action<int> finishedCountProgressAction = default, CancellationToken cancellationToken = default)
+        {
+            var tasks = files.Select(_=> UploadArtifactAsync(api, project, _.path, _.relativePath)).ToList();
+
+            var finished = 0;
             while (tasks.Count() > 0)
             {
                 // canceled by user
@@ -116,6 +148,7 @@ public static async Task<bool> UploadDirectoryAsync(Project project, string dire
                 }
 
                 var finishedTask = await Task.WhenAny(tasks);
+                tasks.Remove(finishedTask);
 
                 if (finishedTask.IsFaulted || finishedTask.Exception != null)
                 {
@@ -123,18 +156,13 @@ public static async Task<bool> UploadDirectoryAsync(Project project, string dire
                     throw finishedTask.Exception;
                 }
 
-                tasks.Remove(finishedTask);
-
-                var unfinishedUploadTasksCount = tasks.Count();
-                finishedPercent = (int)((total - unfinishedUploadTasksCount) / (double)total * 100);
-                reportProgressAction?.Invoke(finishedPercent);
+                finished++;
+                finishedCountProgressAction?.Invoke(finished);
 
             }
-            LogHelper.LogInfo($"Finished uploading assets for project {project.Name}");
 
             // canceled by user
             if (cancellationToken.IsCancellationRequested) return false;
-
             return true;
         }
 
@@ -151,6 +179,7 @@ public static async Task<bool> UploadArtifactAsync(ArtifactsApi api, Project pro
             if (fileRelativePath.StartsWith("/"))
                 fileRelativePath = fileRelativePath.Substring(1);
 
+            
             var artf = await api.CreateArtifactAsync(project.Owner.Name, project.Name, new KeyRequest(fileRelativePath));
 
             //Use RestSharp
@@ -171,7 +200,7 @@ public static async Task<bool> UploadArtifactAsync(ArtifactsApi api, Project pro
 
             restRequest.AddFile("file", filePath);
 
-            LogHelper.LogInfo($"Started upload of {relativePath}");
+            LogHelper.LogInfo($"Started upload of {fileRelativePath}");
             var response = await restClient.ExecuteAsync(restRequest);
 
             if (response.StatusCode == HttpStatusCode.NoContent)
diff --git a/src/PollinationSDK/ManuallyAdded/Client/TokenRepo.cs b/src/PollinationSDK/ManuallyAdded/Client/TokenRepo.cs
index a48e38a8..dd57c7e2 100644
--- a/src/PollinationSDK/ManuallyAdded/Client/TokenRepo.cs
+++ b/src/PollinationSDK/ManuallyAdded/Client/TokenRepo.cs
@@ -18,7 +18,9 @@ public TokenRepo(string refreshURL, string idToken, int expiresInSeconds, string
         {
             RefreshURL = refreshURL;
             IDToken = idToken;
-            ExpiresAt = DateTime.Now.AddSeconds(expiresInSeconds);
+
+            // make it expire 1 mins early so that it refresh token before expiration.
+            ExpiresAt = DateTime.Now.AddSeconds(expiresInSeconds - 60);
             RefreshToken = refreshToken;
             this.LogTokenExpiration();
         }
@@ -52,7 +54,8 @@ private void DoTokenRefresh()
             }
 
             this.IDToken = res.Data["id_token"];
-            this.ExpiresAt = DateTime.Now.AddSeconds(int.Parse(res.Data["expires_in"]));
+            var seconds = int.Parse(res.Data["expires_in"]);
+            this.ExpiresAt = DateTime.Now.AddSeconds(seconds);
             this.RefreshToken = res.Data["refresh_token"];
         }
 
@@ -63,13 +66,18 @@ private void DoTokenRefreshLogged()
             LogHelper.LogInfo("Token refresh finished");
             this.LogTokenExpiration();
         }
-        public string GetToken()
+
+        public void CheckToken()
         {
-            if (DateTime.Now >= this.ExpiresAt)
-            {
-                this.DoTokenRefreshLogged();
-            }
+            if (DateTime.Now < this.ExpiresAt)
+                return;
 
+            this.DoTokenRefreshLogged();
+        }
+
+        public string GetToken()
+        {
+            CheckToken();
             return this.IDToken;
         }
     }