Not Honouring their commitment to pay

On 3-2-2016 our doctor required blood test to the value of R7978 by Lancet laboratories. Lancet did not have a Nappi code / ICD10 codes. I then checked with Discovery Health's call centre if the cost would be covered. After spending over an hour on the phone to explain they gave the go ahead on condition that I supply the practice code and procedure code. They confirmed 3 times that they would refund me from my savings account and that I should pay it first and then claim. They undertook to pay within a few working days. I requested written confirmation but they were hesitant to supply this in writing. After supplying the invoice they refused to pay and insisted on a Nappi code. I then explained what was agreed and they haggled about the format of the invoice from Lancet. The format was then changed and the claim was sent to an e-mail address supp**** by the call centre agent. The claim was then ignored. The call centre explained that the e-mail address provided was not the correct one. It was still ignored. I then consulted with Sandile Phato. Still no answer and they are still delaying the payout with the excuse that they need a Nappi code. I would like them to act as agreed.