The PUK is a SIM security feature.
Your T-Mobile phone features a security setting to protect the SIM card from unauthorized use. When enabled, you'll need to enter a four- to eight-digit PIN code each time the phone is turned on, or if your SIM is moved to a new device. If you've forgotten your PIN or entered it incorrectly three times, an additional security measure called a PIN Unlock Key (PUK) lock will occur. The PUK is an eight-digit number that is unique to your phone. You'll need it to unlock the device.
Instructions
1. Contact T-Mobile by calling 1-877-453-1304. The hours of operation for customer support are from 3 a.m. - 10 p.m. Pacific Time. You'll need to verify your phone number and account password before the representative will release the PUK to you.
2. Enter the eight-digit PUK code using your phone's keypad. Press "OK."
3. Enter a new four- to eight-digit PIN when prompted. Press "OK."
4. Type in the new PIN again to confirm. Press "OK." If all codes were correctly entered, your phone will unlock. Otherwise, the "Enter PUK" or "PUK Locked" message will display again. Confirm your codes and re-enter them as described in the above steps.
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