Vibration stops for no apparent reason

Hello,

I have been using M31S for 3 years.

I have been having some vibration problems for about 6-7 months.

The phone's vibration stops working for no apparent reason. When I turn the phone off and on again, it works for a few seconds but then stops working again. I reset the phone settings, and 5-6 hours later I had the same problem again. Now I have the same problem once a week, I repeatedly turn the phone off and on until the issue is fixed, but this is not a permanent solution.

There is no liquid contact or other damage, the phone has never been opened. I did some research online and found that other people have also experienced this problem, and the available data leads me to believe that the root of the problem is software.

Does anyone have any suggestions for a definitive solution to the problem?