Medihelp medical aid is of no help

My son and daughter were both admitted to hospital, authorization was granted, late by the medical aid, now I receive bills in excess of almost R15000 to R20000 and I am liable to pay for this, isn't this why we have medical aid? To cover those expenses, to get hold of medihelp is a mission and when you email them they don't get back to you, when it's time to take my money at the start of the month the debit orders go off with no hassle, is it worth it being with medihelp? I have had no joy being with the medical aid just endless issues. Absolutely pathetic