Check as follows:

1, forced restart, some softwares occupy unstable system resources when running, which can be solved by restarting. Of course, this only limits the situation of rare crashes.

2. If it still doesn't work, cclean, slim down the phone.

2. If it is still the same, kill the virus and restore the factory settings of the mobile phone.

3, if still, brush the machine again.

4. If this is still the case, it is a motherboard problem, and it is recommended to send it for repair after sale.