NO INVOICE RECEIVED - HANDED OVER!?!?!

THE FIRST TIME WE RECEIVED AN ACCOUNT FROM LANCET FOR A PROCEDURE DONE ON THE 4TH OF JUNE 2015 WAS ON THE 16 NOVEMBER 2015 VIA MMS. My husband was called on the 12th June where he agreed that when we receive the Invoice AND results it will be paid, but why were we called to pay for an account 8 days after a procedure done that the results were not even yet complete as they were for a 21 day culture?!? We NEVER received Invoices/ Statements to settle this bill, it is NOT my duty to run after unpaid, invisible accounts. When phoning the call centre and speaking to your agent Michelle on the 19th Nov, she advised that we have been handed over - I had no notification of this either!?! She also said she would be sending proof of e-mails sent but we are still waiting and honestly if you could send an MMS 5 months later, why couldn't this have been done 2 months and 3 months into overdue. Fedhealth have rejected this claim as it is now stale, they would have paid about R5100 of the R7600. I will settle the R2500 difference of the bill that is my portion and I suggest Lancet motivate to Fedhealth to pay their R5100, due to their total incompetence of following through on unpaid account