Mission impossible to cancel subscription

I subscribed to RMCS late last year (2014) & since November I have been trying to cancel my subscription to no avail. Whenever I call it's either the receiver is picked up & dropped again or sent from pillar to post. When I get someone to actually assist me, I'm informed after capturing my particularls that they'll contact me after 3 days & that is the longest 3 days ever recorded. When I follow up they just start the process from scratch.