Incorrect procedure codes on COVID test invoices

My family and I had to get COVID tests, so we made use of Dischem’s testing facility at Menlyn. I was given 4 invoices which I submitted to my medical aid, but they rejected the claims due to incorrect procedure codes on the invoices. I phoned Dischem and the representative told me that correct invoices cannot be issued. I then emailed them and asked them to escalate the issue, but I got the same response and that “The responsibility remains with the patient to ensure all relevant information is captured correct before any testing takes place”.

I don’t understand how it is my responsibility that they put the correct procedure code on the invoice because I don’t know what it should be. If they offer the facility, then they should have the knowledge to provide the correct medical information. This is now costing me R3400 out of pocket.