It is currently illegal to unlock a subsidised cell phone in the US. A subsidised phone is a phone that was puchased from a carrier (AT&T , Verizon , T-Mobile , Sprint) for a reduced price if you sign up for a 1 or 2 year contract. A cell phone or smartphone that cost $600 and can be purchased through a cell phone carrier for $199 and a 2 year contract is an example of a subsidised phone. Unlocking that type of phone is now illegal in the US.
You can still purchase an unlocked phone or unlock your phone if you paid full price and it wasn't subsidised.
Because we cannot verify what type of phone you have and how you aquired it or verify your identity and whether or not you have a valid service contract with any of the cell phone carriers we do not want people asking for unlocking help and it is against the forum rules to do so.
You will need to go to your cell phone carrier and have them help you with unlocking and setting up an account.