I need a Network Lock Control Key for a Samsung Galaxy S5830D. Where do I get it? My daughter upgraded to this phone and decided later to go back to her old one. I thought I could use it so I had it unlocked by Global Unlock, and used it in the MTS network. Then my son reset the phone to remove her info and then it disconnected from the network and asks for a 'Network Lock Control Key'. Global Unlock says their unlock is permanent; MTS says it is a problem with the phone. Where do I get this 'key'?
Josie