AT&T ConnecTech Unauthorized debits from my bank account Internet

My daughter called ATT regarding computer problems.  She was referred to ATT ConnecTech.  The salesperson asked her for payment of services, and he didn't even fix anything.  The computer wasn't working because her internet service had been interrupted for non payment.  After all that, I started getting debit's every month from my checking account because she used my credit card to pay for the service.  When I called to cancel the service I was given the run around by someone from the other side of the world who couldn't tell an apple from an orange.  That was 6 months ago, and do date, my checking account is still be debited.  They have not cancelled this unauthorized transaction, I didn't give permission for anyone to use my credit card for this purpose.  I am furious that ATT is even associated with such fraudulent activities.  I don't know what else to do accept maybe close my checking account.