PUK codes
The personal unblocking key (PUK) code and the universal personal
unblocking key (UPUK) code (8 digits) are required to change a blocked
PIN code and UPIN code, respectively. The PUK2 code (8 digits) is
required to change a blocked PIN2 code. If the codes are not supplied
with the SIM card, contact your local service provider for the codes.