Help with billing/change of price plan

I just got an increase in price from my 50$ monthly payment to over 90$ now for the exact same service. I think it's because some kind of promotion ran out? However this price increase is insane and there is no way I can keep being a customer at that price nor do I want to. How do I cancel my services as there are multiple other providers out there that can offer at least same speeds at 50$ or 55$. How can I create a direct message to talk to a human and achieve this? I have read multiple threads on the forum that say go to https://forums.xfinity.com/direct-messaging but that just takes me to home page.