Debit order

I'm so angry with clientele I opened a funeral policy with them but the following day I cancelled it cause it was expensive. They never debit my bank account but after 3 months the went to account and debit my account took my last 279 I called them and they told me my policy lapsed the don't why the debited my account they told me they will refund me my money it happened last week Tuesday even today still waiting for them to bring back my money what makes me angry is you can't disbute their debit order you can't cancelled it how is that they can go to your account and take your money but you can't reversed it nna I want money please.