When the temporary lock key did not seem to work, I look in the user manual and saw the info about locking the phone. I entered the code to lock the phone. However, it does not seem to be acting as if it is locked. But, because I still cannot get the temporary lock key to work I wanted to unlock the code. I do not have a sim card from a different carrier as this is my 2nd cell phone and the other phone was also bought at T-Mobile. How do I unlock the phone without a different sim card? Thanks, Karey Spirit