De-activating DSTV service for no reason

I've recently reconnected my DSTV and due to Multichoices' new system, they incorrectly debited my account when the first debit order took place. They have refunded me after a few phonecalls which cost me about R90 in total. For September my service was de-activated twice for no reason! My account is up to date and again it cost me about R60 for phone calls for them to activate it again. Everytime I spoke to the Call Centre I asked why they keep deactivating my account but no one can tell me why.... Well, I would lik Multichoice to tell me why I have to spend almost the same amount on airtime as for my subscription, just to keep my service activated? Please tell me?