financing payments?

I guess I was fooled by the salesman again. I was told I could get 2 lines plus 1 free line when i bundled with the internet. My total would not be more than 200 a month because it's all unlimited. Here I am 2 payments later and it's up to 400! They charged me for changing my due date and then they double billed me before the next bill. On top of that, they are now telling me I have to pay off all my "equipment" (phones, watch, modem) with a financing installment or whatever they call it. I didn't sign up for that.  The salesman lied when I asked if we had to pay off our phones. He said we just had to pay for the taxes upfront, which I did. The total was like 200. First bill was about 205. Then it went up to 300, now 400(next bill). The explanation of all these extra fees is confusing. What happened to all these promotions? The 200 Mastercard they said I would get after 10 weeks to use on my bill or T-Mobile accessories is nowhere to be found or used.