Misbilling and blacklisting

I joined the gym and never used the gym and then i relocated to live outside the country and in which case i had frozen my gym account for 6 months, when my relocation became permanent i phoned the gym and communicated the same to them to cancel it, 1 year later i find that they never froze my membership in fact despite paying the amount for freezing my membership they have been trying to continue with my debit order, to the point where they listed my name with the credit bureau, then i get an sms to say i must rejoin so that they can remove my name, how do i rejoin when i am living overseas. i have tried communicating with the gym directly to no avail. This company has to be the worst in customer service