Why is there no sound when OPPO R9s receives information?

There are several reasons why there is no sound when OPPO R9s receives information:

1. It is possible that the notification in the notification bar was accidentally closed;

2. You can try to enter Settings-Sound and Vibration-Information Ringtone-Select Ringtone to modify SMS Ringtone;

3. If the above operation is ok, you can try it: set the selected information-harassment interception-turn off the message prompt for intercepting strange calls.