Miles refund nightmare

Fit Bit device bought from Dischem using my miles, and device was faulty. I obtained a credit note from the service provider and submitted to Discovery and Dischem. Incorrect miles were refunded and no one can verify where the amount was obtained from. Process started with 3 separate call centre assistants not returning with feedback as promised, or addressing the issue. Need to get the miles refunded to my account, struggling since February 2019. No process in place refunding a client with a 3rd party , BUT no longer my problem. I should get my refund and Discovery can sort the details, since it has now also taken 7 weeks communicating with a supervisor Katlego Mohlokaone. Also speaking to Simone, but each time they 'simply understand'..... and 'we are in discussions with the finance department'. I have been with Discovery many many years and this experience is not at all comforting.