Why sales lies to people and how to resolve it

I was told when I signed up for Xfinity Internet that I would be able to get a cell phone with no money down I just had to wait until after my first billing cycle they wouldn't do a credit check the only reason I will let u know I went for Xfinity is for the cell service I am and have been in a bind for one. So now I activate my service wait a month go to get the phone and they do a credit check and I can't get a phone or any kind of help on it at all not even wen they advertise free on them I have to pay full price out rite to get the phone I can't do this and I have called multiple times when I ask so it tells me to call corporate but I can't find the number and I am really upset . Long story short I want to get what the guy on the phone told me I would be able to and that's that or I'm canceling service if they even care I'm not sure but I will blow up there business on media and social media until something is done about this bc it is ridiculous life is already hard enough without people lying to get wat they want or that quick sale people are out there killing their selves weather litterly or at work bc of everything things need to change people need held accountable and the big companies need to do their part to make America a better place bc we are losing what America was actually created for I believe we are losing the American way and rights so someone please help me tell me what to do before I start something that needs to happen but i honestly don't want to because on the other side people take things to far as well n everything gets out of hand please help me same thing also happened to a friend that tried helping me by putting the account in his name other then they wouldn't activate it because someone used his name as fraud.