Bank took direct debit for my credit card without my permission

Went on my online banking this morning and saw that an unexpected transaction had shown up on my current account. It was only for around €70 but it had overdrawn my account, which was extra annoying because I don't have an authorised overdraft. The narrative was OP/[name of my bank] CARD PAYMNT so I figured it was a mistake by my bank.

Rang up my branch who said they'd look into it, then got back to me to tell me that it was a direct debit payment to my credit card.

(a) I don't have a direct debit set up for my credit card - I pay lumps off it every month using online banking and I ALWAYS pay more than the minimum amount

(b) The amount of the direct debit was around €40 less than the minimum payment of 5% of the balance anyway

The upshot was that the bank person agreed to reverse the transaction and to cancel the direct debit order on the account. I've written a letter to them confirming the instruction and informing them that as far as I was concerned I gave no authorisation for this direct debit payment and I did not expect to be hit with an extra charge for being overdrawn.

So everything should come out alright in the end. But I'm wondering if this was just a slip-up on someone's part or if they could really have set up a direct debit on my account without my permission. I know that I can do it through internet banking but I have to go through additional pass-code protection stuff to do it. And I definitely never signed the mandate.

Has this happened to anyone else?

Have you confirmed it went to your card? It could have been someone else's DD using your account number in error.

Have just figured out what happened -

I paid €130 into the account last month and the minimum payment was €95.14. €65.14 went out of the account and turned up in my credit card this morning. The first €100 went out on the 4th of February and it mustn't have been within the payment period so it didn't count towards the money I paid in that month. (I thought the period went from the 1st of the month til the last of the month) So the €65.14 was the balance of €95.14 cos the bank figured €30 was all that had been paid.

So I messed up. And it may count as a missed payment so I guess I'll have to ring the credit card centre and talk to them about it.

I'm still annoyed about the direct debit I never set up going through but it's probably in the fine print of the T&Cs.

I was planning on setting up a DD for more than the minimum anyway once my new job starts so this won't happen again.

Long story short - I'm embarrassed!