Incorrect charges misleading information

I have a Post Paid account with ATT with 4 Lines (prior to which we were with Verizon for over 15+ years), we have been loyal to ATT for over 4 years now and when I was trying to leave them to go back to Verizon, they told me that if I stayed with them they would give me their Buy one get one free PHONE offer as long as I stayed with them for the next two years, Which is why i wanted to move to Verizon to begin with. So i paid 100% cost of the Phones Upfront instead of paying for them monthly. I repeatedly asked the customer loyalty person who was selling the Phones to me, if that will change my plan in anyway at all and she stated that it will NOT change my plan in anyway at all, so I asked again does this change the monthly payments I will be making to ATT in anyway at all, to which she stated that it will not change the monthly payments that I will be making to ATT in anyway at all. I repeatedly asked if the monthly bill will change in anyway at all and she stated that my monthly bill will remain the same since I am paying off for the phones in advance. Since we were told nothing will change, we decided to stay with ATT and pay for the Phones upfront---

Since I have direct payment option with ATT, I noticed that my bill went from about $140 to $310 first month and $140 to $315 second month --I was certain this was a mistake so decided to call ATT on August 25th - I was on the phone for over 4 hours and spoke to pretty much all departments you possibly have. Each depart said it was another departments mistake and they will be able to fix it- one operator said they will fix each months bill at a go-nothing happened---I was told time and time again on Saturday that a Supervisor/Manager will call me right back...NOTHING--No managers/supervisors were available apparently at all till the very end... A manager finally took the phone and spoke to me. 

When I finally spoke a supervisor/manger he repeatedly lied to me telling me they heard everything I was saying to their representative and that I was making things up, so I asked him that while I was repeatedly asking for a manager why didn't he just get on the line and speak with me to resolve the issue that I am having, I asked him again and again that if they heard the conversation that I was having with their representative, then why would he not get on the line and speak with me because I know that if I was to wait for him to call me back that they would actually never call me back, just like before I know that their customer service department has promised several times that their manager will call back and they never call back. 

I asked them so many times since they record all conversations to give me that recorded conversation and show me that I was not misled by their representative and to show me that I am wrong, to which they said it takes days to pull that record out and that their manager will call me after they have reviewed the tape of that recording and will let me know, I was told on Saturday that by Sunday afternoon or Monday Latest, I will hear back from a person in authority.  I am still waiting and there is simply no response back to my query!

ATT promised me that they would keep my bill the same prior to us Purchasing the Phones upfront- I was told it's like buying a phone from a store, YOUR plan WILL NOT BE CHANGED!!!  At this point I am getting the same service I was getting two month ago but for the first month I am being over charged about $170 for the first month and $175 for the second month and God only knows what I am being charged for the current month. 

I was told you will have to stay with ATT for next 2 years, and I have no problem with them. We were told we could get the phone offers if we add a line, or  get Direct TV ...I did not want to do that--I made it very clear, I just want to buy one get one free phones, since that is the offer that i was getting from Verizon. and finally I was given the offer that as long as you Pay for the phones upfront and stay with us for two years --NOTHING on your plan will change ---

To which I stated that I am only willing to buy these buy one get one free phone ONLY and ONLY if my bill remains the same, to which they said several times that my monthly bill will not change---

I have called a few times to almost all departments and got into several heated arguments to be able to speak to a manager and I was informed that a manager is not available and that they will call me back. I am still waiting for that call back today is Tuesday evening  (August 28th) and have been waiting since Saturday morning (August 25th, 2018) to get my charges refunded.

At this point I am still waiting to hear back while incurring extra expenses in my families budget by almost over $345 + this months charges could be $170 more or $175 I can hardly GUESS...

I would appreciate a refund on the over charge of about $345 and I request that my bill be changed back to the original price of about $145 a month (which it was prior to June 16, 2018)