FNB in arrears themselves.

I called the loans department to find out if I qualify for the payment break this January. They told me that it is in arrears by R1, something. How is this possible as the debit order for R972.97 went off. What was in arrears as we got paid early in Dec and there is still money in my account so what in the world is FNB on about R1. Also you cannot ever get hold of collections as they say low staff volume and the line just cuts off, so who the hell should I speak to to sort this out as nothing was in arrears.