Old mutual 9203

My biggest mistake was to to sign up with yhis funeral cover. I've been canceling this policy over 8 month's now because it has a tendency of taking money from my account randomly so. After i canceled this policy at 1st, they took money from my account 3 times. Then i disputed via my bank, after 2 months again they found a way to take money. And now 4 months later i wake up to a debit from them again, after I've disputed and blocked them... Should I change bank accounts now? After reversing money that was taken, there will also be bank charges now. This is theft