Sports and Fitnes horrible treatment

I joined the gym, and on my first day I went in and got injured inside their spinning class. As per DR.s advised I had to be in cast and physiotherapy and not be active until she was satisfied. I brought this up to them and ask if they can kindly cancel my membership, they refused and what makes me me more angry was that they didn't even apologise. They continued to deduct for 12 months. I WILL CONTINUE SPREADING MY HORRIBLE TREATMENT I INCURRED.