ATT changed my contract from 2 year to month to month plan and now over charging me

I changed from Sprint to ATT on 11/29/2015. Over the phone I was trying to get the best deal. We went back and forth a number of times eact time the ATT rep coming with more discounts to  make me change to ATT.

Here is what was agreed:

$160/ month, two year contarct, 3GB (we wanted 2 GB only ), 4 lines,  $200/ per line reward on each line credited to my account after three billing cycles and a $100 gift card , and reduce ny home phone and DSl by another $30. Originally ($65 with taxes).

I was told that  4 new phones were eligible under the contract and the cost of the phones would be  approx $185 total for all the 4 phones with activation fee waived. I paid for the phones upfront by credit card the same day.

I activated my phone on 12/6.

Uverse guy came and installed u verse  internet on 12/27.

I called customer service to enquire about my bill mid of JAn. Was told that the bill was emailed to me at a different email acount which presumably was created when the U verse was installed. (I had an ATT account where I paid  for the ATT home phone and DSL) I checked the bill at the other email account and was surprised to see the bill amount $693 which in short included the $40x4= 160 activation fee , more importantly I had to pay thirty instalments for the 4 phones at $73.60 per month etc. 

I called ATT and explained to them all the above  and bottom line they  give me a discount of $280  but still put me in the monthly contract at $130 per month, pay for the phones at 73.60 instalment for 30 months and the uverse home phone and internet at $52.50 to give a total of $266.10 next bill. The first bill I will still have to pay $413.24 , (They said I am eligible for the $200 gift card and that they would credit my bill for $600 after three billing cycles.). 

The best part is that the phone is a used phone , the bill states certified like new for the three samsung S5 phones.The i phone 5 appears new.

Have been calling ATT numerous times, one rep asked me to go to ATT store to get the 2 year contract. I went to the store but they said they cannot do that and suggested I call ATT rep and so on. It is over a month now. My bill is a unified bill with uverse and cell phone together. I asked them to break down the bill so that I can pay uverse seperately till the cell phone dispute is settled but ATT cannot do anything.

I cannot cancel as I had to cancel within 14 days. How would I know the changes if the bill was emailed to me more that 14 days of activation?

Where do I seek  redress to resolve this cell phone problem?