INCORRECT INFO ON INVOICES SUBMITTED TO MEDICAL AID!!!

I have been struggling to have my son's hospital stay bills from Pathcare sorted for more than 6 months now - my son was in hospital since he was born up until 10 weeks later when he passed away - we had an auth number from the med aid - which should have been used on all his forms whilst he was there - his hospital stickers with all the relevant info as pasted on everything he owned - even the Pathcare forms - but for some reason Pathcare messed this up...he had numerous blood draws and tests done through them and when they have submitted invoices to our Medical Aid - some of the bills were paid out of the "in hospital fund" , while others were kicked out due to them submitting invoices on his father's dependent code ... after picking up this error - I went back to them over and over again to advise this - they just didnt really care that it was their error and tried to make it my responsibility!!! THIS IS UNFAIR AND WRONG... they have now handed the accounts over to a LAWYER and I received a call today. I don't feel like this is my responsibility as they HAD all the info at their finger tips and probably due to a "back office " issue THEY ARE THE ONES THAT MESSED UP AND SHOULD CORRECT IT!!! it is NOT my duty to run around now to get auth numbers from the medical aid so they can resubmit - as now I'm being told the accounts are "STALE"!!!! AGAIN NOT MY PROBLEM SORT OUT YOUR **** AND GET MY "FILE" back from the LAWYER...THIS IS YOUR ERROR NOT MINE!!! I HAVE SENT EMAILS AND I"VE CALLED THERE...AND ITS STILL NOT SORTED!!!