Product: Debt collection

I have 3 accounts on my credit reports listed under Merchants Credit Guide. I originally disputed the accounts with the credit reporting agencies and they simply came back as verified. I received the dates of service from my credit report and I called my insurance to confirm that they were paid. For services provided on XX/XX/XXXX, my insurance received a claim from XXXX XXXX XXXX XXXX for XXXX. I paid my copay of XXXX, my insurance negotiated and paid XXXX. MCG is collecting for the " disallowed amount '' of XXXX. For services provided on XX/XX/XXXX, my insurance received a claim from XXXX XXXX XXXXXXXX XXXX for XXXX. I paid my copay of XXXX, my insurance negotiated and paid XXXX. MCG is collecting for the " disallowed amount '' of XXXX. For services provided on XX/XX/XXXX, my insurance received a claim from XXXX XXXX XXXX XXXXXXXX for XXXX. I paid my copay of XXXX, my insurance negotiated and paid XXXX. MCG is collecting for the " disallowed amount '' of XXXX. My insurance told me that for these 3 dates of service, I did not have any remaining financial responsibility. They told me this practice was called balance billing and Merchants Credit Guide was in the wrong for trying to collect. 
I called Merchants Credit Guide on XX/XX/XXXX and I relayed this information. XXXX, the first agent I spoke to, refused to listen to the information that my insurance company provided and insisted that my insurance company did not know what they were talking about. She advised that she would send out documents for these 3 accounts and provided me the following account numbers : XXXX, XXXX, and XXXX. That evening, I also prepared written requests for debt validation and sent them via certified mail. On XX/XX/XXXX, I reached out to the creditor listed on the collection accounts on my credit report, XXXX XXXX XXXX. Through several phone calls and emails, I was told that they no longer had a contract with the emergency room I visited. Their contract ended in XXXX and all files they had were transferred to Merchants Credit Group. I called Merchants Credit Group again and tried to find out who owned the accounts. During that conversation, XXXX advised that she could not help me. I had asked questions she did not have the answer to. She transferred me to her manager, Mr. XXXX. Mr. XXXX told me that the documents I requested on Friday were already placed in the mail on that morning. I told him the information my insurance company provided and I also relayed to him the information I received from XXXX XXXX XXXX. He assured me that the information XXXX provided was inaccurate and he would get in touch with his contact. That same evening, I provided him the email were XXXX XXXX XXXX advised that they no longer held my account and everything was transferred to Merchants Credit Guide. I called the next day to make sure he received my email and to, maybe, get the name of the correct creditor and he told me he would have to research the information and get back to me. He also told me that he had not received my email from the prior evening because XXXX mail attachments and XXXX  were incompatible by design. I told him that since these accounts were in dispute, he should remove all 3 from my credit reports. He advised me that I could legally ask for them to be removed through a dispute with the credit reporting agencies. We ended that call and I forwarded him the email attachments through my business XXXX  address. I left him a voicemail to let him know the email was sent again as he requested.