Hyundai motor finance POOR CUSTOMER SERVICE!!!!! San Diego California

I've been with Hyundai for over 6 years and I'm leasing a second car now through Island Hyundai. On my first lease I had over millage and I was told that I would receive by mail an itemized breakdown of the over millage, which I never received. Hyundai claimed they sent a letter and called me, and I never received either. Unfortunately, I found out through my credit score notifications I was past due on a payment. After I notified Hyundai to dispute payment about not receiving the bill they were rude with poor customer service. I've wrote letters to all credit bureaus and Hyundai. I've payed the bill and now my credit score and report is ruined. I’m always on time with my car payments and never missed a payment so this is clearly an error on their end. Hyundai was sending the over mileage bill to the wrong address so therefore they should provide a Good Will letter to say I'm in good standing with payments so it's removed from my credit report. I also checked my online account and billing address, which had the correct address. I will never lease or purchase another car from Hyundai again due to what they did to my credit report.