Cancel my membership!!!

I joined planet fitness in February this year and I haven’t been able to attend the gym since due to health reasons. I was on vitality and the membership fee was discounted hence I joined. I then tried to cancel my membership after a month or two but I couldn’t and now I’m suddenly told that I’ve been handed over but I haven’t even gymed even once!!! I find this totally unacceptable and unfair! I was sold a dream and lies and now I must pay for something I didn’t even use!!