Re: My Galaxy S3 keeps asking for the SIM/PUK number.
Uh-oh... I've had this happen to me before. It's not particularly fun.
If the phone will let you, dial 611 so that you can reach customer service. If it will not permit you to do so, dial 1-800-331-0500 from an alternate phone. CS will be able to help you with the PUK code.