I am making a POST call to a server running VS Console app using the Retrofit with OkHttpClient on an Android device (Android Studio app). I have the following setup for Login Activity:

LoginRequest loginRequest = new LoginRequest(username, password);

            Call<LoginResponse> call = placeHolderApi.loginUser(loginRequest);

            call.enqueue(new Callback<LoginResponse>() {
                @Override
                public void onResponse(@NonNull Call<LoginResponse> call, @NonNull Response<LoginResponse> response) {
                    if (response.isSuccessful()) {
                        LoginResponse loginResponse = response.body();
                        if (loginResponse != null && "success".equals(loginResponse.getStatus())) {
                            Toast.makeText(LoginActivity.this, "Login successful", Toast.LENGTH_SHORT).show();

                            Intent intent = new Intent(LoginActivity.this, MainActivity.class);
                            startActivity(intent);
                        } else {
                            Toast.makeText(LoginActivity.this, "Invalid username or password", Toast.LENGTH_SHORT).show();
                        }
                    } else {
                        Toast.makeText(LoginActivity.this, "Error: " + response.message(), Toast.LENGTH_SHORT).show();
                    }
                }

                @Override
                public void onFailure(@NonNull Call<LoginResponse> call, @NonNull Throwable t) {
                    Log.e("LoginActivity", "Authentication failed", t);
                }
            });

I am trying to handle this error:

Authentication failed                                                                                                   java.net.SocketTimeoutException: timeout                                                                                                    at okio.SocketAsyncTimeout.newTimeoutException(JvmOkio.kt:146)                                                                                                  
at okio.AsyncTimeout.access$newTimeoutException(AsyncTimeout.kt:161)                                                                                                    
at okio.AsyncTimeout$source$1.read(AsyncTimeout.kt:339)                                                                                                     
at okio.RealBufferedSource.indexOf(RealBufferedSource.kt:430)                                                                                                       
at okio.RealBufferedSource.readUtf8LineStrict(RealBufferedSource.kt:323)                                                                                                    
at okhttp3.internal.http1.HeadersReader.readLine(HeadersReader.kt:29) etc...

The VS app on server is correctly receiving the logginRequest from the Android device but the loop is always entering “onFailure”. Is there any solution ? I tried to send message from Server to Android app, it works so I don’t know why there is a network problem ? Thank you