Poorest and unproffesional service!

I am super annoyed by the poor their poor service, on the 10th of July my loan with them was settled, on the 15th they went and debited my account, when I called to rectify this I was told that they could not do I refund on the amount that was debited as there was a possibility that I could have under paid, they needed proof that shows that I had paid the account, I emailed this proof, today when I call a gentleman by the name of Stefan tells me that he can't help me because my account is in the debt review department, the last time I checked I was not under debt review which is why they were able to give me a loan, now i've been holding for the debt review for the past 10 minutes! can Direct Axis help me understand how they were able to give me a loan if I was under debt review and can they please refund my money as I had already paid them