Will disconnect from debugging mode when reaching break point

Question

I created a simple app and start in Android Studio version 3.6.2. I have N Android 10 real device and when I create a break point in onCreate(), Android Studio jumps to the break point successfully, but after 5 seconds it will disconnect from debugging mode automatically without any error or log. I searched a lot about it but I can't find out why it will disconnect automatically. Has any one had this problem in real Android and how can I solve it?

This is my code

Button btntest;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        btntest=(Button)findViewById(R.id.btntest);

    }