Failure to capture payment

Very poor service from DirectAxis. My wife has a loan with them, her debit order went of on the 06th February, now they harrading her, want to send people to collect stuff from us, blah blah blah. She has received numerous calls where she told them that the debit order did go off the bank, she even send them a bank statement to prove that it has gone off. Now she face bad credit record because of this. Really the worst ever service from big companies like this. My wife is so furious and do not know what to do from here. She mailed them 3 times, she spoke to ay least 20 people there, and no one listens to her. I strongly recommend them to no ome else. They are useless.