More than 2 months to pay back a simple claim

I have spent the last 2 months trying to get a claim refund from Discovery for a PMB consultation which should have been paid in the first instance. A new 2019 out of hospital PMB application was sent and then eventually approved. My banking details were updated as well. I had to phone Discovery again today, only to find out they now also require a proof of payment that I did indeed pay the specialist. No correspondence was sent to me from Discovery regarding this prior to my call. I sent through the PoP to claimsadjustments(at)Discovery(dot)co(dot)za. Thereafter, they sent a cryptic email stating 'We only received a receipt as proof of submission report.Please include the related account and refax it to.....'. This is an unclear message and very unprofessional to say the least. I sent an email asking what is actually required. No reply. I phoned the call centre, and no one was able to assist me. The matter was just escalated to the PMB department via the agent. I need to know what the problem is, why Discovery is so reluctant to pay back my money?? There is simply one excuse after the other. Your complaints procedure on your website also does not work at all, even though most of the steps have been gone through. Nothing has been resolved. I need the matter resolved and my money paid back WITHIN THIS WEEK. Please attend to this matter ASAP.