Non refund of service providers account

On the 9thSept I visited an Orthopedic Surgeon . I was invoiced R 750 for consultation and then R 300 for two injections I paid the Doctor and submitted the two invoices to Discovery for the refund . They paid the R300 in full.and nothing for R750'consultation . I queried this and after numerous emails I was told that the Doctor cannot use two invoices with the same code . I then found a help on the net and I was told to go and get a consolidated invoice and resend it to claims adjustments . This was done . Response was the account had been paid previously . Now some 10 or 20 emails later I get an email asking if I was satisfied with the way my problem was solved . I rep**** no as it was not refunded my money . I then get a call from a lady who said it was a code problem but she would contact the Doctor and sort the problem out . About a week and a half later I phoned the Doctor who confirmed that Discovery had not contacted them at all . By now I want to pull my hair out . Two emails to Mujeeb have not generated a reply so I have given up . This has happened to me on numerous occasions so I recon Discovery Health to me are the most frustrating organization I have to deal with.