Discovery does not pay approved claim

My daughter was involved in an accident with my car on 01 May. Discovery's Claim Department were excellent to process the claim and my vehicle was repaired within 2 weeks! Just after the accident my daughter was attacked by the other driver and he broke my vehicle's key. I replaced the key at a cost of R1 750 and emailed the invoice and POP to the Claims Dept who immediately returned an email stating that the amount will be refunded into my bank account within 3 days. This never happened. After numerous calls, I was told that the payment was approved, but that my bank account no was incorrect. I told them that I had changed my bank details online using their App. They again took my new bank account details, but nothing happened. It has been 3 months now and I have made over 20 calls, each taking at least half an hour, without any success. It seems that the department that processes the payments either does not exist, or is somewhere in another galaxy far away where nobody can or is allowed to talk to them. What must I do, since I have sent so many emails ans made so many phone calls, but still my refund has not been resolved, or anybody returned my communication?