Multichoice have been debiting money from my account, more than once

Multichoice have been debiting money from my account, more than once. I tried to reverse and block but they still manage to go into my account and ***** money. When disputing a debit order i get charged extra amounts. They debited 339 on the last day of September when i paid cash already. I dont know why cant they cancel this thing, i want back my money. This is annoying.