Before flash your call phone at first you should check your device hardware problem. if your device have any hardware problem you should fix this problem first then flash your call phone.
if you flash your device use USB cable make sure your call phone battery is not empty. if your device battery is empty and if phone is turn off without complete flashing device will be full dead.
Download Free Upgrade Flash File For Nokia 2690 (RM-635) you should use always upgrade flash file for your device. if your phone is dead, auto restart only show Nokia logo on screen. when open any option phone is auto restart. you need to flash your phone. download this flash file and solve your problem.
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