That's ridiculous - I've never heard of anything like that before. I hate working with debt collectors and feel your pain... I hope T-Mobile has some type of response and they should take care of everything... Sorry to hear that
The salesperson misrepresented the Carrier Freedom program.
To clarify, T-Mobile does not pay your ETF or EIP directly. You must be prepared to pay your previous carrier's final bill out of pocket. The amount of reimbursement that you receive from T-Mobile depends on whether you have an ETF or EIP, the type of device you buy from T-Mobile, and the trade-in value of your previous device.
I suggest reading through the details of the Carrier Freedom program, and calculating how much you should get vs. what you received. If there is a discrepancy, contact T-Force.
To contact T-Force
Go to the Contact Us page and use the Facebook, Twitter or Google Plus link under in the “Social Support” section.
Ouch! This should have gone much better for you.
I agree with e2k's suggestion of contacting T-Force. They're a great group of account experts and will do everything they can to help you out with this.