Fnb not quick in replying when they must payback.

This is the worst experience since I have started banking as a teenager. We have been under debt review. Due to inexperience staff our accounts with Absa and fnb was over paid. I went into Absa to resolve the matter and was ask some security questions and confirmation of banking details and within a day the money has reflected in my account. Then it was fnb and oh my word 4 months later we are still struggling to get refunded. What is so bad there is no communication from who or what so ever. We have included fnb complains department in our email, but nothing came from it. This was not money that I owe fnb, it is ours. If the roles were change I surely would've recieved letters of demand from attorney's. I was contemplating on moving my banking over to them, but hel no. We gave yhem a deadline that the money must reflect in our account no later then the 14th December. Thus far no no communication from their side. Is this a professional institution whom people are entrusting their finances to. Think twice