Direct debit top-up option blocked

Hello O2 community,

I urgently need help.

on 4th july i recharged my O2 sim card with 9.99 euros + 4.99 euros. Money usually gets automatically deducted later after my order is placed.

But then i realized immediately that my the bank account details which was already added and used previously was closed down a week before and so i changed immediately to the new bank details.For the amount of 4.99 euros got deducted from my bank account on 9th july.But for the amount of 9.99 euros it didnt got deducted automatically from the new bank account and i donot know why.

But today i received a message that my sim card is blocked and i need to call them.

Now i donot know where to call as i cannot find any o2 contact number. please help me in knowing how to unblock, otherwise it will be a big problem if i cant make any calls.

My German is not good so if I can resolve this issue online it will be great.

got the below msg:

Dear O2 customer, the direct debit you requested with the E2E reference xxxxx was not redeemed by your bank on 07/12/21. Unfortunately, your prepaid credit was not sufficient to offset the outstanding amount of EUR 9.99 and the return debit fee of EUR 4. Your direct debit payment is temporarily suspended and your SIM card is blocked for chargeable use. Please call us to compare your bank details.

Your o2 team--