Complaint sub-issue: Their investigation did not fix an error on your report

My mortgage was sold 4 times since original purchase date of XX/XX/ 2004. I have been making payments automatically from my bank account since purchase. Just realized that my credit score is around 600s and there is no reason why my score can be that low as I am never late on payments. Very good payment history with the lenders paid off multiple cars multiple times no issues there either. I checked to see what makes it so low, come to find out XXXX I guess previously called XXXX XXXX who are known for screwing homeowners for many years and tons of complaints online they have been reporting me late on my mortgage every other month or sometimes multiple months in a row for over a year. I called the company and I was told because my payment changed and it was short $ 10- {$15.00} for a few months instead of notifying me that the payment is short they start reporting them late and would not apply the payments for that current month, hold the payment until I pay the next month then they cover that shortage from that months payment apply that to previous month and make the full payment and report me late for the current month. Because I don't check my credit as often as I should I never realized they ruined my credit and because of them I pay high interests on cards and would not qualify for a loan which I was about apply for a loan for a commercial property for my business. 

So, I called them they said I am late on payments and that I am one month behind, and I told them I am never late on payments and that can't be true, I told them I have every single statement since I purchased the house and confidently I said I can prove them they are wrong after multiple calls realizing the tone in my voice they realized that they cant fool me they said not missing payment but my payments were short then they said I have {$560.00} unapplied funds, because I was short for $ 10- {$15.00} for multiple months instead of letting me know writing a letter to cover the shortage they chose to let that ad up to a total of {$210.00}. I always make $ 10- {$15.00} extra every month just to be safe and not that it is much but thinking at least it would go to principal. But what was I thinking it wasnt even covering my payments according to them, But why would they do this because they want to ruin peoples credits then they can charge higher interest rate as many mortgages are adjustable rate including mine, and there are stories similar to this online from many homeowners. So the total of {$210.00} supposedly that I owe them is not an issue I am sending that payment right away just send me all the statements where I was short but I am sending you that payment right away just write a letter to credit agencies that I wasn't actually late there was a shortage which was paid in full, and they said no. I said that is not fair ruining honest peoples credits for such a small amount especially when the mortgage has been paid since 2004 even with all the mortgage crisis there was no problem with the payments and they said no. I tried to speak with a supervisor and they actually put me on hold for minutes then the line got disconnected. I called them again of course start to explain everything from scratch and this time I asked them to also provide me with my note as these people are the forth mortgage servicer since purchase, I wondered if they even have my note. They said they are emailing it to me as we speak after confirming my email address and said they will send a copy in the mail too and still have not received anything neither on my email or regular mail and it has been more than two weeks. Before we hang up I told them if this is not going to be resolved I will seek other options and one being writing a complaint with Consumer Financial Protection Bureau, and the person on the phone was very careless and I was told I can do what I choose to do. 

So as a conclusion, XXXX previously XXXX XXXX ( I assume same company ) intentionally ruins peoples credits, they want you to fail so they can benefit from it and they have no willingness to solve the problems that they've created in fact they seem happy that they achieved their goal of creating another bad credit customer.