my discount Credit remove & increased monthly plan

I'm in the same boat. I agreed to a 24 month contract and discounts just seem to disappear without notice. This is like the 3rd time. They do not seem to understand what the word "Agreement" means. Spent an entire day messaging, talking (mostly screaming "we have an agreement") to a rep and then a 'manager'. Unpleasant and useless. He's going to get back to me with options. I should have stayed with what I originally wanted and paid full price. I can't believe that a multi-billion dollar corporation is acting like a conman with bait and switch. But here we are. I'm retired so I don't have a lot of money but I do have an unlimited amount of time. And a lifetime of collected customer service anger which I am hesitant but willing to use. If I end up paying extra I'm going to make it 'interesting'.😠