LabCorp review: Billing

I have an HSA provider who I use to make payments in my behalf from my HSA account. LABCORP charged about $100 for a lab test, and the bill was paid over 2 months ago. LABCORP started sending Collection Notices that I haven't paid. I checked with my HSA provider and they sent a FAX to LABCORP a month ago. Still another collection notice was sent again demanding payment. I had my HSA provider send the FAX again but also include my name, labcorp invoice # and my birthdate. Days later, I logged into the web portal for labcorp, and they still haven't acknowledged any changes to my account balance.

I also requested my HSA provider to send me the same FAX that they sent to LABCORP. I will take this document and send it with the collection notice. My fear is that they will refer the bill to a collection agency before I have a chance to send documentation to them.