Posted by JohnBoy on February 07, 2001 at 10:08:31:
Get a letter from them admitting their mistake and stating that the payments have been made on time and were never late. Then take that letter to the credit bureau in your area and they should be able to change it immediately. Also have them request in the letter that the credit bureau delete the inaccurate information and correct it, naming all three major credit bureaus.
That would only take care of the one credit bureau, which ever one that is in your area. The other two major bureaus you will need to send them a copy registered mail, return receipt requested!
This letter should also satisfy the lender you are dealing with. Then again, if they are brain dead it may not! 
If the finance company says they can’t give you anything in writing admitting to THEIR mistake, they are LYING! If that happens, explain to them that you can get approved on your deal even though their information being reported is incorrect, but your lender said you will have to pay an extra 4% on your interest rate over the life of the loan. Tell the finance company if they don’t get this taken care of by YESTERDAY, AND, give you something in writing to help you get this corrected NOW, that you WILL be forced into taking the loan at the higher rate to prevent from losing your deal and THEY will be sued for the cost of that 4% you’re being charged for because of THEIR mistake, over the next 30 YEARS!!!
That should get their attention!
If you have to, send them a certified letter also to let them know you mean business and how serious their mistake is!