Planet fitness is requiring premiums after my contract with them has lapsed

I signed a two year contract with Planet Fitness which expired in February 2020 just before lockdown and this cruel company went on to dedust premiums without my permission. I then called them to report this matter and I was requested to send a cancelation email which I did even though I did not see the need as our agreement was over. To my surprise I received summons that I was handed over to their lawyers for the R2000 thatI owe them.