IPhone 3g problem with charging?

I listened to radio with my iPhone 3g then it charged out and then I tried to charge about 2 hours and it nothing charged.

I have the same problem. If it is not a charging cord issued by the apple store, it is not used for charging, only for playing music. So if it is not apple brand and something else like Griffin cords and chargers, return it and get an Apple cord. Also, if your cord is damaged by the connector or you yank your charger out by the cord and not the plastic piece, you could damage the wires inside. Another problem that could occur is the metal piece inside your iPhone could have snapped or been damaged by frequent use, meaning that you should try 6 different chargers and have no effect. What you can do is bring it to Apple and have them take a look. Hope this helps, I'm really with electronics!

Mine did that also. You have to restore it thru iTunes. It's not a cord issue. There's something about it loses memory that it has a battery and has to be factory restored but you have to do it thru itunes. If i remember correctly plug it in to the computer and hold the power button like 20-30 seconds. Itunes will detect it and then do a restore. Hope this helps. I found out how on youtube. Very common problem.