If you enter the wrong PIN more times than the maximum number of attempts allowed, your SIM card will become “PUK-locked.”
You need a PUK code to restore access to
HTC Jetstream. This code may have been provided by
AT&T when you received your SIM card.
On the keypad screen, enter the PUK code, and then tap
Enter the new PIN you want to use, and then tap
Enter the new PIN again, and then tap