Discovery refusing to pay for covid related tests after they sent news letter saying all cobid related tests and treatments would be paid for

I was sent to hospital by my GP at night as she thought my blood was clotting.I called medical aid and the voice-mail says if its an emergency you must go.I went through casualty ,the doctor could not admit me as my results said I had covid.The hospital beds were full.Discovery said they would pay for covid related tests etc in a news letter they sent.Now they refuse to pay my lancet account as the hospital visit was not authorized.I could not get authorization as they don't answer phones and tell you if its an emergency go.It was an emergency because the GP called me at 9pm and asked me to go to the hospital urgently.