Refusal to Pay back Rental Deposit by Respublica Student Living.

I paid a rental deposit of R5000 for my daughter in January , now that my child has moved out of their residence she is entitled to get her deposit back. I have called them and written them emails but they are not responding, Their system of requesting refunds keeps on saying we don't have enough credit. I need that deposit to use it as a deposit in January for another residence.