Cannot claim back

Recently went for an eye test and took the Woza Woza deal as medical aid cover very little Al good and back home submitted the invoice to the medical aid and the medical aid cannot process the claim as the codes incorrect. Specsavers then came back that the do not provide the codes on a cash deal. Having paid cash for meany cases before this is a first. And it is leaving me with far bigger bill to serve. My advice be very carefull