Sometimes during too much of load my PC automatically restart during working so that when I logged in again then it reset my PhpStorm settings.
Does anyone knows how to get rid of this?
Sounds like phpstorm is working as intended. If you shut down your computer suddenly the applications don't have time to save their state correctly and you can get corrupt data. In this case your settings might become corrupt.
If you can't fix your computer (it sounds like a cooling problem) then export your settings from phpstorm and import them again after your computer has restarted.