Contact Service Provider message

I was trying to use a T-Mobile SIM on my NEW V3, as soon as I try entering a code under the Sudsidy messege a new message pop uo that says Contact Service Provider. I call Cingular (current Service Provider) but they could not do anything to help. is there anything that I can do to reset the unit to ask again for the Subsidy?

Cingular locks the V3 so u cant use another provider's SIM card in them since they have exclusive rights to the phone for 90 days. If it is locked u probaly have to go and have it unlocked so that ur able to use another SIM card. It costs about $25 or so to have it unlocked.