app/src/main/java/com/example/notifyservice/MainActivity.java

@@ -129,7 +129,6 @@ public class MainActivity extends AppCompatActivity implements PostRequestCallba
     protected void onCreate(Bundle savedInstanceState) {
         Log.i("a", "1"); // STATIC
         super.onCreate(savedInstanceState);
-        unregisterReceiver(notificationReceiver);
         notificationReceiver = new NotificationReceiver();
 
         setContentView(R.layout.activity_main);
@@ -613,6 +612,7 @@ public class MainActivity extends AppCompatActivity implements PostRequestCallba
         Log.i("a", "onDestroy"); // STATIC
         super.onDestroy();
         try {
+            unregisterReceiver(notificationReceiver);
             unregisterReceiver(smsReceiver);
         } catch(IllegalArgumentException e) {
             Log.i("ppp", Arrays.toString(e.getStackTrace()));