Product: Debt collection

I have been trying to clear up an ongoing billing and unethical issue with my XX/XX/2022 date of service for months. I have talked to XXXXXXXX XXXX the billing company and the collections department, XXXX several times. The first time I spoke to XXXX, a person called me back and advised me that my bill would be written off. Another person hadnt realized I spoke with someone and the same conversation of a write off occurred. 
Still though, I receive statements and text messages asking me to pay my bill from my XX/XX/2022 office visit with XXXX XXXX. I do not deny this visit, however my appointment was for a XXXX  as advised by XXXX. XXXX had seen me twice for my XXXX XXXX and for a XXXX XXXXXXXX XXXX XXXX. They advised me to see XXXX XXXX for my XXXX XXXX XXXX XXXX XXXX XXXX 

On XX/XX/2022 I sent a letter certified to the billing company address and the facility. I attached email from XXXX advising me to call XXXX XXXX and schedule my XXXX Despite that this was terrifying to me and it is my very first XXXX I did so. The appointment was set and they said that they would obtain my images before the appointment. XXXX confirmed it was for a XXXX and had my paperwork filled out upon arrival. The person at the front desk at XXXX set me up and at no time upon arrival did anyone tell me I would not be getting a XXXX or that there was a bill for the facility. At no time upon arrival did anyone tell me that my images were not available. The negligence started at this point, or before I arrived. I had taken off of work for this appointment a biopsy. 
In my private room at XXXX, XXXX XXXX came in. Immediately she apologized because there was an error on her part with the computer imaging. She did not have them ready for my appointment and therefore, I would not be able to have the XXXXXXXX I was scheduled for. This was absolutely not okay that I had taken so much time out of my day, now unpaid and was told that the visit was pointless. It doesnt cure the possibility of XXXX either. XXXX XXXX advised me to return in a few months, without ever even looking at my images. She admitted that there was a mistake, apologized and left. 
XXXXXXXX XXXX did not dutifully provide me with proper care. It was only explained to me that there were several problems on the providers behalf when I was in the private room with the XXXX. No one with the administration ever bothered to tell me, call me, formally or casually explain that I would not be getting a XXXX. I am a person, I am not a code on a medical bill. I have the right to make my own decisions. The physician and location have a duty to provide services based on the appointment that is scheduled. If the images had a huge problem with XXXX 's end, if the appointment was not scheduled correctly and if XXXX failed to inform me of that then that is something that you will need to handle accordingly. I dispute this bill, I dispute the facility and I dispute the organization put into my visit. 
I dont understand why I continue to be ignored in my letters or not followed up on with the write off when I speak with people. When I call the billing company, their agenda is merely to argue with me. The person says they understand but then will say the coding is correct. She even went so far as to say I had a XXXX No. No. No. Politely, no. 
After I sent my certified letters, I recieved a robocall. I explained everything and the representative said she could completely understand. After the call, I received a bill from the collection agency, XXXX. I sent them the dispute on XX/XX/2022 with the same letter I sent explaining the fraudulent billing.