Product: Credit reporting, credit repair services, or other personal consumer reports

I am not sure if you can help, but I XXXX XXXX XXXX in XXXX and requested to set up a payment plan with our hospital via their website which has a request form. I made a one off payment of {$75.00} on XX/XX/2018, the day I made the request. The hospital ( I am told in XXXX ) referred the bills related to me ( but not baby, even though they were acquired at the same time ) to XXXX because apparently, they never received the request to create a payment plan. They weren't even aware the option was on their website because apparently, another company manages the website. 
Regardless, I got a call from XXXX and immediately called the hospital. They told me they would look into it but I didn't hear back. After getting another call from XXXX in XXXX, I called the hospital direct again and they told me they couldn't sort it out via the website and to just set up a payment plan over the phone. I made another one off payment on XX/XX/18 of {$110.00}. I also made a payment towards my baby 's outstanding account, which had not been referred to XXXX. I agreed to pay the rest of the balance on both accounts off in 3 more payments ( XXXX, XXXX and XXXX ). I asked when I set this up if it would stop the calls from debt collection and they told me it would. XXXX called me a number of times again over the summer and during a XXXX phone call, told me I needed to set up a payment plan with them. I told them I'd set up the payment plan with the hospital, they said I had to set it up with them. I advised them that I would not pay a company I knew nothing about calling me to tell me I owe them money ( thinking it could be a scam ) and I told them I would call the hospital direct and verify my payment plan. I called the hospital who again told me that the payment plan was in place and everything was fine and I should no longer receive debt collection calls. In the meantime, I made the following payments on my account : XX/XX/2018 {$120.00} XX/XX/2018 {$120.00} XX/XX/2018 {$120.00} This cleared the total balance, which now show {$0.00} outstanding and is fully paid. I also paid off my baby 's account ( not with XXXX  ) at the same time. I received another call from XXXX about 3 weeks ago and I ( again ) explained I had a payment plan in place and they confirmed they could see I was paying the balance down and told me I shouldn't receive anymore calls. 
I received an email from XXXX on XX/XX/XXXX telling me my credit score had decreased due to a collection placed on it - I checked and it was XXXX. I called them today ( XX/XX/2018 ) and explained that I had a payment plan in place with the hospital and requested the collection to be removed. I was referred to a manager named XXXX, who refused to remove it. She told me that because the payment plan was not set up directly with XXXX, it did not meet the " minimum payment guidelines '' and that they would not remove the collection on our credit score. I asked to speak with someone else but she refused to refer me on to anyone and told me nobody at their company would remove it, I would have to speak to the credit bureau direct. I don't know what else to do. I have worked *extremely* hard to build my credit score up from 0 because I moved here from the XXXX 4 years ago and had to start from scratch. I have 100 % on time record of payments and this collection will remain on my score for 7 years. I set up the payment plan, made regular payments and paid the debt off as agreed with the hospital ( who did NOT tell me that I needed to set the plan up with XXXX and who confirmed more than once that the payment plan I set up with them would stop the debt collection calls ). 

I called a national law firm that deals with this, but I have to pay them to help me and can't afford to do that. Is there anything you can do to help? I am so furious and frustrated because I have been so unfairly treated and to make it worse, XXXX gain nothing by refusing to remove the collection from my record, even though I did everything right. I did not understand that I was supposed to set up payments with them, mainly because the hospital ( who I owed the money to ) told me I did everything right. Additionally, I NEVER received ANY documentation from XXXX in the mail. I only every received numerous phone calls. With all of the scams going on right now, combined with being told by the hospital that everything I was doing was correct AND XXXX  employees telling me they could see payments were being made, I thought I did everything I needed to do. 

What can I do? 

Thank you for your help, XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX, NM XXXX XXXX XXXX XXXX