Product: Vehicle loan or lease

I received an end of lease bill from GM for the amount of {$3600.00}. I knew that I had went over in mileage and I agree to that charge of {$1300.00}. I also agree to the disposition fee of {$390.00}. The remainder of {$1900.00} is wear and excess is completely false. I have never in other leases ( 3 total ) ever had a fee like this. I brought my XXXX truck to two different XXXX dealers ( XXXX XXXX & XXXX XXXX ) for review and end of lease look over, both agreed my truck was in excellent condition. NEVER, was I told an appraiser from GM will look at it, that's why I brought it to two dealers. I was getting it appraised, valued right???? When they left to look at my truck I was 100 % sure they were assessing my vehicle. When they returned, I was told the vehicle was in excellent condition. I called immediately after getting this ( bill ) to try and come to a conclusion so we could both move on. GM also put this on my credit report and it is now reporting late. This as of today dropped my credit score significantly. I am in total shock. This isn't even late as they were suppose to get back to me. The date on the invoice is XX/XX/XXXX19. Today is XX/XX/XXXX19, not even 20 days? I have called and called to get this matter resolved, but they never call me back. My call history goes like this : XX/XX/XXXX19-Called to dispute excessive wear, said they would call me back. XX/XX/XXXX19 ( spoke to XXXX XXXX She had no new info for me yet, will resubmit my dispute. She also told me my truck was inspected 1 full week after I had dropped it off ( I included my drop off receipt ). XX/XX/XXXX19-Called ( spoke to XXXX ) She said no answer yet to my dispute of wear charges, she will look into it and call me back by Friday XX/XX/XXXX19. XX/XX/XXXX19 ( spoke with XXXX ) She said no new updates in my file, she will send email to XXXX and promised to get back to me by the end of the day. Called again on XX/XX/XXXX19 ( spoke with XXXX ) I said today this is due and I am waiting for the mileage to be corrected so I can pay them that. I emailed her the correct paperwork of starting mileage of XXXX. They have a different number of XXXX. I asked if the dispute on wear and tear has been looked at. Still nothing. I asked for a manager and then got on the line with XXXX ( XXXX ) this was a number she gave me. She stated that while they recalculate the mileage they can give me a payment plan. She promised to get back to me. I told her that a loan was now on my credit bureau with them. I stated that this isn't a loan but rather a bill from GM. She assured me this isn't something that will hurt my score. As of today XX/XX/XXXX19, my credit score dropped 43 points. It now shows late on XXXX XXXX. My credit history is flawless til today. I am in need of help. I also found out that someone at the XXXX dealer that works in the auto body department also was just hit with an excessive wear and tear on his lease return. If this is happening to people who actually work for GM, this may just be a huge issue. Imagine the money they make by XXXX you into damages, and ruining your credit ( you can't dispute these, even as my truck sat on a dealer lot for 7 days ). You can't dispute them because GM owns the appraisal company too. I asked for the appraiser info only to find out they won't give it to you. I look forward to hearing from you!!!!