footsbanger80 , if the battery is not holding a charge or charging replace the battery as it could possibly be the issue. If battery good and still having the issue, try a factory reset(link below) as a Installed App/software/etc., may be corrupt causing the issue. Good luck. I hope this helped you out, if so let me know by pressing the helpful button.
http://www.hardreset.info/devices/zte/zte-grand-s/