I took the battery out even took the screws of from the back cleaned it out with a little brush
and dried it with the hair dryer .
Works good again
Normally a result of liquid damage, especially since you mention using a hair dryer and the problem goes away, this may be short lived as corrosion will start effecting the phones. Symptons of liquid damage can be, row of keys on keypad not working, phone indicating headset mode or car mode, phone indicates it is charging yet it is not.