Should be reported for ***** & Harrasment

After paying on the day of the service we received, AND we had to pay first before we could get helped, we are now getting emails about an outstanding balance, even though we paid in full for the service. After numerous emails and that they were going to be reported for *****, they found their mistake. BUT now they are doing the same thing with my wife, who went on the same day as me, and paid for the service, just like me. We even showed our bank records to show that we paid.