Why does Apple 13 only vibrate once after receiving three short messages?

The reason is user settings, the time interval of receiving SMS or system problems.

1. User Settings: Turn off the "Vibration" option, or adjust the vibration intensity to the lowest level, so that you can only feel the slightest vibration and hear no sound.

2. Time interval of receiving short messages: The receiving time interval of multiple short messages is very short, so Apple 13 will treat them as the same short message, and only vibrate and ring once.

3. System problem: Apple 13 system has problems, resulting in abnormal vibration and ringing. At this time, you can try to restart the iPhone or update the operating system to solve the problem.