Overcharging ambulance fee and late billing

My husband had a seizure in July and was transported to hospital, the paramedics were amazing, but it seems the accounts department have major issues.

In Nov we got a bill (5 months later) to pay the excess immediately! First bill we had received according to our medical aid we have been overcharged by R1500. According to Bonitas there was a contract with Netcare 911 at the time of the incident. We should therefore not have any excess payments. Also Bonitas only received and processed their agreed portion on the 13th of November 2022.

We should not be made to pay for others incompetence but only for any portion that is due by us according to contract ie Netcare 911 should only be charging the contractual amount .

Nobody seems to know what is going on, and as the client we are totally confused. We just want it resolved and complete clarity to be provided.