Medical aid changed co-payment after it has already been paid and patient already discharged. Now I can't claim the right amount from the medical aid

I am highly upset in how you dealing the issue and records on co-payments. I would think as a staff member we would get better treatment. On 12 Aug my husband has been admitted to the Louis Leidpoldt mediclinic. I had to pay a co-payment of R5490 (R1830 for admission and R3660 for a procedure). I paid it. My husband has been discharged on 21 Aug. After this date I asked for the authorisation letter to have it on record and then see that the co-payment is not the R5490 but R1830. So the medical aid waivered the co-payment of R3660 after my husband has been discharged. Now I don't have proof from the medical aid that I paid the full co-payment of R5490 and I will not be able to submit my claim from GAP cover. I urgently need this money because that was my money to buy food! The medical aid said that the hospital need to refund me. The run for that account was on 13 Sept and I phoned the hospital today, 19 Sept and the funds are not reflecting in their account yet! I am furious because I need my money. And my husband has been admitted again on 30 Aug and now the hospital said that they need to settle that account as well before I can get my refund. This is not on! How can you change the co-payment after my husband has been discharged and after I have already paid this co-payment. This is your admin nightmare that you need to fix. I need my money. Somehow you need to ensure I get my refund. These co-payments are extremely high and this is our food money we pay and now you messed it up. Membership nr ***