Unpaid invoice by umvuso medical aid

This medical aid is unprofessional has given me a lot of grief firstly they said they would not authorised my request for sterilization because they want papa smear done then after they said my doctor must write a motivational letter for procedure and they sent me consent form on my email to sign it for images before they allow me to get the procedure done.now as I am saying they demand pictures of my internal organ to send them with my email and I don't have them and they never talk to my doctor about images before and after procedure, now I had to pay all the hospital bill and general surgery that is not fair the hospital want me to pay but I have medical aid.As a South African consumer I cannot pay the medical bills that umvuso medical aid is liable to pay for