you'll need to ring your provider... i.e - 02, Orange, depending on what network and talk to them. or just get a new sim? 02, orange, t-mobile etc, all do free genie sims.
to get your puk code just go to like the website of the company your with... such as o2.ie... I'm irish so its .ie... and you can get your puk code there if your registered and if your not registered then register cause you get free credit
Just a suggestion, but it's often a good idea to read a thread before you reply to it...
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