AnytimeFitness Can't Cancel Membership San Antonio Texas

I opened my membership with AnytimeFitness under a 2 year agreement that converted to a month-to-month. The month-to-month was converted during COVID. After a few months of charges, I tried canceling. They would not allow me to cancel and would not return emails/phone calls. They required us to come in person to cancel in writing.

I had sent several emails and left messages again, none of which were returned and so I stupidly thought my membership was canceled. We changed credit cards in this process and I didn't think of it. I got a notice today from a debt collection service for 6 months of membership. I am now trying to navigate this and all their manager would say is that I still have to follow their procedures and they were "very" supportive of people during that time