FNB documents not good enough for Discovery Medical Aid

Discovery does not accept the FNB Payment notifications as proof of payment. I had doubly paid for the services of a Anaethetist for a Hernia op. i.e I paid her directly in error not knowing that Discovery was going to meet the claim. Her app Healthpartnerinfo has got the claim reversed. FNB has not helped my send Discovery what discovery regards as proof of payment. FNB's chatline, which I can't now access wasn't helpful. I am working on a laptop not a cell phone