If you purchase goods with a gift card you can only refund the goods back to your agc. If you are talking about cashing out an AGC (to CC) there is no option to do so.
If I want to cash out my agc balance I do the following:
- Get the account banned
- Call amazon and tell them you have money on your agc balance that you wish to withdrawl
- They will send you a check
Hope this was helpful!