Ampath *****ently charging more after you get a quote and make payment

This is the worst for accounting. i went to pinehaven to do my blood tests. they gave me a quote but said that it was fasting so i had to go back the next morning. Wilgeheuwel was on my way to work so instead i went there. as my medical aid is exhuasted i had to pay upfront. first they gave me a quote that was R600 more than pinehave quoted me. same company so i showed them the quote from pinehaven and she apologized and corrected it. i paid by card on the day to do the test. now i'm getting a bill from ampath 2 weeks later for an additional amount. how can some new charges appear after i was quoted. you can't just make up prices after someone has paid. so either their quoting system is faulty and needs urgent repair or this company is *****ently and actively trying to ****** the people using their service