Billing problem no solution

If I could rate Lancet 0 I would definitely do that. Did my bloods a year ago, while there the guy at the counter told me that my medical aid is covering my bloods. 1 week later I received an sms saying I must pay R165.10 which I did, then 3 months later I receive another sms I owe R875.10 for my bloods which my medical aid did not cover all of a sudden. I have been sending emails to lancet since January because I want to know what I paid R165 for if they just send me the full bill, and keep in mind there was two different ***, how I don't know. Till this day no one has fixed this, everything week there is someone else replying to my email then I have to explain the whole situation all over again. Honestly don't know how they operate at lancet but something seriously need to be done !!!!