Product: Vehicle loan or lease

When I first leased my car they told me my due date was on the XXXX of the month. I told them I get paid twice a month and my rent is due on the first so I needed it to be due on the XXXX like all my past leases. They said I needed to pay the first paymement and then I could call to move the due date. They said there was a grace period for payment so it was okay if I was late the first time. I was late as I told them I would be and called to change the due date to the XXXX. They did it NO PROBLEM. Next month comes around I get a bill for the XXXX again. I call, they say oh it sometimes takes a cycle to change. No worries it will be on the XXXX the next month. I pay late because I was assured the month prior the date was changed and they said it just takes time but they can see the request in my file. One time I had even paid but it wasnt showing up on their end due to 2 a lag from 2 back to back holiday they were closed but I had proof and Confirmation to provide it cleared my account I had to provide before they would stop calling my work who I told them not to call numerous times because Im not allowed calls and told them to remove that number. The said the would but never did and kept calling and getting me in trouble with my boss. They would call sometimes 10-20 a day even when they said I was off that day. This goes on for a few months. Finally they say oh you need to sign a request to change let me send that to you. I receive it, sign it, send it back and it happens again ... I try changing the date on line instead of calling. Same thing. Today I get the mail, no change AGAIN! Im fed up. I call, same story. I say Im not doing this again. I want to speak to a supervisor. Im put on hold for a half hour. Then someone comes on and says you are late we cant change the date until you are current. I explain, Im late because each month you assure me you have changed my date and you dont. I feel like you are doing this to collect extra fees. I know you have record that I have made a request EVERY month since I got the car because the representative told me she can see each and every request listed in my account. She said yes, I see that too but we wont change your date until you are current. I say Im current now. She then says but your next bill is due in less than 19 days so we dont have enough time to change it. We can change it if you pay your next bill and then request it. Its the same difference and the same amount of time. She refuses to give me the name or contact information for someone above her and said nobody else can or would help me. I insist there must be someone else I can speak with she said no! She is the end of the line. I believe they are refusing to change the date to collect late fees. I have never been later than the 15-20 day ( not sure how long it takes to process ) I just want a simple 15 day due date change. In all my prior loan for 3 cars I was NEVER late. I have done this date change a million times with many different types of companies and never once did it require more than a simple phone call. I tried to go all the way up the chain of command today and was on the phone for over an hour but they refused to move the date.