Debit money from your account even if you canceled

I've canceled my contract with rain 2 months ago, because I got fiber (reason is because the ten days before your debit order rains signal gets so bad you cant to anything on the internet). But yet for 2 months rain have been taking money from my account. I've requested a reversal because i want my money back. But they just ignore my requests. You cant reverse the debit order, your bank doesnt allow it. So good luck if you choose rain, they take your money.