Product: Consumer Loan

I am having terrible experience with Ally Financial. They are asking me to pay for damages that I am not liable for or is within acceptable wear and tear and also they have wrongfully reported negative remarks to credit bureaus. Not to mention poor customer experience and near harassing experience. 
It all started within couple of months of me signing the lease. I had set up auto payment but within couple of months they sent me past due invoice with few cents outstanding. I called them right away to find out what happened. They said some taxes/fees had gone up after I signed the lease. But they also said instead of changing my monthly payments that was already set, I can simply pay the total outstanding payment when I return the car. Since the amount was small I decided to hold on as suggested. 
When I finally returned the car to a different dealer, for several days I did not hear from them. I called Ally to find the status. They said they have not received any update from the dealer. I called dealer but they said they completed paperwork same day. I called them back, that 's when they said they have received it and will get back with final statement within couple of weeks. 
In the mean time, I received an alert from my credit monitoring service that a past due payment has been reported by Ally in the amount {$21.00}. I was shocked. At the same time, I received final statement by mail, I was even more shocked to see that they have listed XXXX damages and asked me to pay for them. 
I called them again to ask why it was reported as past due when I did not even receive final invoice and additionally it was already agreed that I will pay the small delta when I settle final invoice. I also told them I was aware of only XXXX scratch on the left rear bumper and that too was within the size of circle they said will be acceptable. I also told them the other damages I had never seen and I am sure they must have been caused during idle parking at dealer 's place when there was no action taken. They did not have any explanation and took it for additional research and said they will get back within within a week or so. 
I called them again after a week. Call got redirected to asset recovery and agent asked me how do you want to pay the outstanding balance without even asking what I am calling about. I told them I want to find status of dispute first before talking about the payment. Then the agent looked into records and said XXXX of damages has been waived but not the scratches on the rear bumper and on the front bumper. When I asked why, the agent was forcing me to believe the size of scratch was more than size of the circle as seen in the picture. I explained it was certainly not the case as I can also see the same picture. There were XXXX parallel lines of scratches, each less than the size of the circle but when you try to fit the XXXX lines in the same circle then they will go little more than the circle. I said I am aware of that but the contract clearly says size of each scratch has to be less than the circle size so why are they combining XXXX separate lines together. He said thats the final resolution. I asked what are my options to ensure the final resolution is impartial and not be same finance company. He did not provide any response to that. I googled myself to locate how to seek help in such situations where finance company claims to have final judgment and hence submitting this request to investigate and help. I paid every single payment on time, took very good care of the car. The additional payment was only few cents that the company agreed to be settled later and I am ready to pay when the invoice comes but still they reported to credit bureau. My payment history and credit rating has been XXXX If their contract said multiple lines of scratches will be viewed in combination, I would have fixed them too myself.Still I am finding it difficult