Terrible service during my pregnancy

In Oct 2021 i was sent by my midwife to do my standard /normal prenatal test that everyone does at the start of the pregnancy. I now get a bill from Lancet for R1175 saying that discovery did not pay for it and i need to pay for it..When i call discovery they say Lancet ICD codes are not covered as it does not match theres. No special test was done just a prenatal standard test like the HIV, RUBELLA, ETC. How can it be that you do not for for the standard prenatal test done. this is really terrible service from discovery. I had a baby 3 years ago with discovery and also had to do the standard prenatal test and it was covered. I even still have pregnancy test cover available under my maternity benefit and this is what im been told. Discovery you have really messed me around in this pregnancy with the cover.