guard let httpResponse = response as? HTTPURLResponse else {

            throw Web3Error.unknownError
        }

        guard 200 ..< 400 ~= httpResponse.statusCode else {
            if 400 ..< 500 ~= httpResponse.statusCode {
                throw Web3Error.clientError(code: httpResponse.statusCode)
            } else {
                throw Web3Error.serverError(code: httpResponse.statusCode)
            }
        }

Author: mtc1146

Sources/Web3Core/EthereumNetwork/Request/APIRequest+Methods.swift

@@ -120,11 +120,15 @@ extension APIRequest {
     public static func send(uRLRequest: URLRequest, with session: URLSession) async throws -> Data {
         let (data, response) = try await session.data(for: uRLRequest)
 
-        guard 200 ..< 400 ~= response.statusCode else {
-            if 400 ..< 500 ~= response.statusCode {
-                throw Web3Error.clientError(code: response.statusCode)
+        guard let httpResponse = response as? HTTPURLResponse else {
+            throw Web3Error.unknownError
+        }
+
+        guard 200 ..< 400 ~= httpResponse.statusCode else {
+            if 400 ..< 500 ~= httpResponse.statusCode {
+                throw Web3Error.clientError(code: httpResponse.statusCode)
             } else {
-                throw Web3Error.serverError(code: response.statusCode)
+                throw Web3Error.serverError(code: httpResponse.statusCode)
             }
         }