need help with contacting TMobile corporate office

Reading these threads I realize I am not alone. T-Mobile told me multiple lies. I have lived up to my end of the contract which I unknowingly entered into. I pay my bill on time every month yet they haven't lived up to anything on their end. That can't be legal. T-Mobile should have to be accountable just like I would be if I stopped paying my bill. I guess nobody has been able to find a way to speak to someone that has the authority to hold them accountable. One thing I think is crazy is they set up a brick and mortor store in a town where the surrounding towns can't get service. I wish I could take them to small claims but I can't afford to.