Why is there no sound when oppo sends text messages?

The setting method of OPPO SMS ringtone is as follows:

ColorOS3.0 and above: "Settings >; Sound and vibration >: information ringtone ",you can choose to customize the ringtone or the system's own ringtone.

Tips:

ColorOS 1 1 and above, in order to avoid long-term ringing of information ringtone, the user-defined information ringtone file will only be played for the first 5 seconds at the longest.

Due to different models and system versions, the operation path may be slightly different, please refer to the actual operation interface display of the mobile phone.