my sims card is locked how do i unlock it

[Android Central Question]

my sims for my straight talk service is no good can I put a t mobile sims in my lgh700and it work it says its locked now how can I get it unlocked and will I have the same phone number if I want

 

[B. Diddy]

Welcome to Android Central! Are you sure it's the SIM card that's locked, or is the phone locked to Straight Talk?

A SIM lock is placed by the user. Is this your card, or did you get it from someone else?