puk stands for personal unblock code, you dont want to fool around : "If the wrong PIN is typed in more than three times, either the SIM card, the device or both become locked. They can be reverted to their original unlocked state by entering a PUC, provided by the service operator through verification. If the wrong PUC is entered ten times in a row, the device will become permanently blocked and unrecoverable, requiring a new SIM card. Cellular phone users are therefore advised by most providers to keep their PUC written down in a safe place separate from the device."
Yes you need to call Tmobile support and tell them you need the PUK code to unlock your device. Please pay close attention to the numbers and * and # codes you need to enter or you can lock your device forever.