Cedar Dental Clinical

My child received orthodontic care from Orthodontic Care of GA, Cascade Rd. office. She finished her treatment and I made my final payment to them in August 2018. This final payment was confirmed by they guy Tremaine at the time and cited that I had $0 balance. An entire year later, Cedar Dental Clinical l, LLC, whom acquired Orthodontic Care of GA is calling me telling me that my account is past due and I owe them money. On 12.16/19, I spoke to Christine who tells me that I still have a balance but the amount is unknown and she would have to get back with me. But made it known that I would be paying them any balance owed to them. On 12/17/19, she calls me back advising that they were missing payments but that still doesn't account for my balance of which she still couldn't tell me what it was. I advised her of my last payment in August of 2018. I advise her that I kept with my payment plan of 2 years and I owe nothing and the final payment of $51 was the amount given to me by Tremaine to pay my account off. She CONFIRMED that she saw a note in their system by Tremaine of the payment and balance in full and since it was noted in the system that they will have to honor. I just got a bill of $350.00 that they are demanding that I pay. I can't account for any mismanagement when acquiring a new company. Not to mention, my last payment of $51, which was not even my normal monthly payment was the amount given to me by the office to pay my balance off.
Product_Or_Service: Orthodontia