Debit my account when they feel like it

I bought a lounge suite from Morkels September 2014 and signed a debit order. The leather lounge suite is actually cheap plastic that is torn everywhere after a year. I've been trying to get Morkel to look at the look suite but nobody is interested in assisting me in this regard.<br> <br> I signed a debit order for the montly installment. This month agents have been calling me daily to tell me my account is up to date???? yesterday a consultant called me again to inform me that my account is now R24.00 in arrears. Not sure how this can happen if I signed a debit order.<br> <br> Also this morning I've noticed that my account was debited with a payment for Morkels last night (10 December). I've signed a debit order for the last day of the month and dont understand how they can just debit your account when they feel like it. <br> <br> There is not much you can do when Morkels is just not interested in helping - I can't stop paying the account as that will affect my credit rating.