Oppo SMS has no sound. How to recover?

SMS ringtone setting method: ColorOS 3.0 and above: "Settings >; Sound and vibration >: information ringtone ",you can choose to customize the ringtone or the system's own ringtone. Tips: For ColorOS 1 1 and above, in order to avoid long-term ringing of information ringtones, the user-defined information ringtone file can only be played for the first 5 seconds at the longest. SMS vibration setting method: 1. Go to settings >; Notification and status bar > notification management > find the "information" APP and click to enter the information setting interface > information notification > turn on the vibration switch. "2." long press "information" app > application information (details) > notification management >; Information notification > just turn on the vibration switch. "This answer applies to all OPPO models.