How to fix iPhone or iPod touch if it’s not charging

Wall charger is needed for the process* 1.Turn ipod or iphone off 2.plug in to wall then device 3.leave for 2-3 hours AFTER CHARGING 1.Press menu button twice.If screen doesn't come up that means it worked. 2.turn on device 3.if it still shows 20% battery reboot and it should come up as 100%. 4. You are welcome