How to get T-Mobil to honor their agreements

I was offered a promotion. Month later, had to call to find out why it was not applied. I was told the original rep made a mistake and I had to upgrade my plan. IF IT WAS ME THAT DIDNT HONOR THE AGREEMENT, I WOULD BE IN COLLECTIONS. Reluctantly I upgraded my plan. Month later, still no promotion and I called again. Was told that the promotion was only available through the Apple store but it would be fixed...mind you, I already traded in my old phone so impossible to get it back. Never fixed, no promotion. Called again this month and was told the promotion is only for a different plan and needed to upgrade the plan again. Aside from all this, a total of 6 lines were activated on my account over the last year without permission and when I called to get it fixed, I was still charged for the time the lines were active. On top of that, protection plans keep showing up and I have to keep calling to get them removed. 

This is not only a breach of contract but also unfair and deceptive business practices which I cant seem to get anyone to help with. Totally one sided. Just a large corporation taking advantage or average people with bait and switch tactics, and hidden or surprise charges. 

IVE BEEN WITH TMOBILE FOR 10 YEARS AND NEVER HAD A PROBLEM UNTIL NOW. If this doesn't get resolved, I will sue T-Mobile and cost the corporation more money to defend than it would to just do the right thing and honor the agreement bargained. THE CORPROATION AS A WHOLE MIGHT NOT CARE ABOUT IT BUT I IMAGING THE STOCK HOLDERS MIGHT BE UNHAPPY ABOUT SPENDING MONEY FOR SCREW UPS AND BAD PUBLICITY FOR A TARNISHED BRAND. Fortunately, I am a lawyer so don't have to spend money but will cost my time and it is sad most people would just be forced to pay through collections. 

BAD BUSINESS TMOBILE.