Problem after problem with no resolution

I am a service provider who submits claims to many of the schemes under Medscheme's administration on a regular basis. Previously, I have found them to be efficient and good payers. However, from the start of 2018 I have had nothing but problems. Claims are rejected for all sorts of reasons, such as the referring doctors' information not being on the claim, when the information is all present and correct. Alternatively, claims are just not paid and I never receive any remittance even after resubmitting them 3-4 times. My receptionist spends hours on the phone reporting issues and getting reference numbers, only to have to re-report the same problematic claims the following month when nothing is resolved.

I have never had such consistent and frustrating issues with Medscheme and am at my wits end trying to get the problems resolved and get my money in before the claims become 'stale'.