Client-Server communication

I’m developing NREAL application for Android.
I would like to do client-server communication with the PC(VSCode/C++) as the server and the android phone as the client.
However, the application you create will work on the Unity emulator, but not on an Android phone.
If you know how to occur this problem, teach me please.

Hi, could you please print log and check if there is any error report? Also, please tell me the specific phone model, Android version, Nebula version and SDK version. Thanks in advance!