lancet does not update there system n ow i must pay for their stupidity

i went to lancet lab for blood test two months ago. the gentle men checked on his system and said the medical aid will only pay for certain test i must pay 270 i paid r270 now i get a call saying i must pay 400 rand .yet the guy is saying lancet didnt update there system. we work hard for our money and you these people just trying to take money from us.its makes me furious.