Genova Diagnostics previously Great Smokies Diagnostics Trying to get money they aren't owed Ashville North Carolina

I was told up front that I needed to pay 159.00 and that is all I would be charged.  Then I received an "East Pay Statement" saying I oweded 150.44.  The invoice showed that my insurance had paid several amounts but when I looked online and then called my insurance neither I nor the person I spoke to at the insurance company could find any claims relating to Genova.  Strange.  When I talked to Genova they said that my insurance had paid and then the only answer they would give to me asking if this 150.44 is now due is giving me repeatably a quote saying we are not allowed to answer that question.  We can tell you that this invoice is a good faith effort and that I will receive one more and then would never hear from them again and they would not contact a collection agency.  They also said they had an agreement with my insurance to make a good faith effort to collect.  I have absolutely no trust of this business.