Stale claim due to unforeseeable events

Good day team, This complaint is not directed specifically at Discovery Health per say as I understand that there are Scheme rules that must be app**** for the sustainability of the Scheme for all of it members, however on occasion I feel that the enforced of said rules is app**** unfairly. While I understand that a claim is stale after 90 days I cannot control how long a medical institute will take to supply me with the claim. it should be noted that I requested this on numerous occasions from the medical institute however they only supp**** it recently, as this is a state facility I understand that speed is not of paramount importance to them but I called them repeatedly to follow up on the claims and lookout for my claim statement to see if it reflected. Now the claims has been received for Rand Clinic it has in accordance with the Scheme rules and CMS guidelines has been rejected as its outside of the 90 day period. This seems unfair as I cannot think of what we could have done differently to avoid this situation. All that they say is that things were busy during Covid (usual story everywhere you go) and because of this I will be 20k out of pocket. Please can someone assist me with this and consider paying this claim?