FNB bad customer service

I have always received good customer service from FNB, but after our bond was cancelled/ settled they are still deducting debit orders. I've tried to phone them to follow up, after I've emailed them as well as informing them telephonically, but no answer. I've already lost more than R50 worth of airtime, by just holding the line because nobody seems to answer when you call ***. They also didn't refund me my balance, only after I had to call them after numerous attempts were I rebursed the balance. Now they are still deducting debit orders.