Promotions Department blatantly LIE to secure sale. SCAMMERS

Earlier this year, I saw a promotion on the ATT website saying you could get a free iPhone XS, if you added a new line. I called to inquire about this and was transferred to the promotions department, where I spoke to some lady with an Indian accent named "Rose" or some similar fake name. I asked if I could cancel one of my four existing lines either before or after adding a new one to receive the promotion. She said I could not do that, BUT she could do me a favor, "since the Promotions Dept have special access that stores do not" and get me the free phone as an upgrade without adding a new line, so long as I paid the taxes upfront. This sounded a bit fishy so I asked, "there will be no additional lines added, and no monthly charge for the phones?" she confirmed and restated those same words and told me that I would see a $30 monthly charge for the iPhone XS but I would also receive $30 in credit each month. I asked her to confirm there would be no additional lines added or any additional monthly charges, and she confirmed once more and told me my bill would stay the same other than the taxes she charged upfront. I agreed because why wouldn't I and she offered to add another phone as another upgrade on one of my other existing lines and of course I agreed after clarifying ONCE AGAIN, and being assured AGAIN that there would be no additional line added and I would receive credit for the phone every month. I agreed and decided to get add an s10e for my wife for some more money upfront to cover taxes. She told me she just had to confirm with her supervisor that it would be okay to get me this special deal, put me on hold, and when she came back she brought another girl, who verified I was the account holder, then read a whole bunch of agreements and confirmed the purchase. For the past 4 months I have been paying for 2 LINES, each costing $35/MO (for reference, the iPhone XS as an upgrade would have been $30/Mo and the s10e $22/Mo!) and they are being UNUSED. I do not even have the sim card for them. Now if I want to cancel the unused lines, I have to pay FULL PRICE for both the phones upfront, not subtracting the $35/Mo I've been wasting just to own them. After about a DOZEN calls to customer service, the promotions department, fraud department I have not been given any help other than, "keep paying $35 for the next 36mo until the monthly credit finishes paying off the phones, or say good by to the $280 you've spent over the past 4 months on unused lines and pay full price for both phones upfront." (over $1,800 in addition to my $400 monthly bill) I absolutely cannot afford to drop $1800 on 2 new phones, that I would've never dreamed of buying new if they were not offered for free +taxes. I am at a loss for words, I figured it was too good to be true but I didn't think a huge company like AT&T would do something like this. I am losing $70 a month because I literately can't afford to pay $1800 upfront and cancel the lines while still paying rent and feeding my kids for a month. Can anyone please help me??