Bonitas refuses to pay a claim for R6000 timeously lodged

Bonitas does not want to pay the Drs account for services rendered in April 2021. They are saying that the account is stale yet i have provided them with proof that the claim was lodged in April 2021 by the Dr. They have been giving me a run around for almost 2 month's. On the 17 Dec 2021 i spoke to their consultant Katlego who advised me that the claim has been referred to their claims assessors for a review . Today i followed up via email and the autoreply was that the claim has been rejected as it was stale. I then called them just after 15h30 today so that i can be put through to their complaints Unit but the consultant made me to hold for about 20 minutes and then i got cut off, she never bothered to call me back.