LIBERTY THE WORST MEDICAL AID EVER

In April 2014 I fell pregnant and I had been on Liberty Medical Aid 2 years by then so I thought I would be covered NO PROBLEM. I was wrong unfortunately! In December my current gynae had to go for an emergency operation and after that retired. So I had no choice but to go find another gynae that would take care of the birth being December this was not an easy task as most doctors where fully booked or on holiday. I found another doctor who was available but unfortunately out of the network - I phoned the call centre for authorisation spoke to a lady called Anita who assured me that the birth with the new doctor would be covered in full because this was not my fault. I received the authorisation code for the birth and all went well however a month down the line I started receiving bills from the doctors that Liberty would not cover. I have phoned Liberty with every bill I receive and all they tell me is that these doctors were not within the network. Shouldn't I have been told this BEFORE getting the authorisation code?I have now had to resort to resigning from Liberty because I cannot afford to pay all these bills and be on medical aid.