Unhappy [Q] JiaYu G3 freezes random when locked, have to pull battery

Hello Guys!

I recently got an JiaYu G3, very happy with it, fast phone etc.

My problem is: When locked it randomly freezes and i can't unlock it. (screen stays black, If there's a message, the red light blinks normally.)
To get it working again i have to pull the battery and reinsert it.. and i have to do this 5 ~ 6 time's a day.. very frustrating.

Does anyone have an solution? :c

Sorry for rubbish english (Dutchie)