Promotion not honored- Only way out was to cancel

So I had a promotion with Xfinity for two years $40 a month with 300 M BPS speed. Another Internet company approached us last month offering a better deal. So I reached out to customer support at Xfinity and inform them of the better deal so I was offered double the speed at the rate of $35. I was told that initially it will show up as $60.00 on my end but as of a week later that will auto correct to 35$ after the deal gets accepted. So I called the next week after I realized that this did not happen and was informed by one of the customer representatives that such a deal cannot be offered and I can try to call after a week to see if there are new deals. So I spoke to a representative a week later whom offer to make some changes so I'll end up paying around $45. However two days later I still noticed that this did not happen. So I called customer service and informed them and again their answer was there is nothing they can do the best offer would be $60.

I have been lied to not once but twice on text with screenshots to prove it and their only answer was that it's either I pay this or I have to cancel there's no other way around. I wasted multiple hours with these people. They didn't even honor their word the first time and not even the second time. This is a bunch of scam that needs to be reported and Federal Trade Commission (FTC) and needs to be stopped.