Product: Credit card or prepaid card

I have been an customer for many years. Since having this card I have had an automatic payment setup for automatic withdraw from my bank account. Around six months ago ( XXXX ) I was notified that they payment was showing as late. I called customer service two different times that month to get this issue taken care of and to see why the payment was late if I had it set to minimum payment from my bank account ( which had been coming out ). The person I spoke with updated my payment method made the account current and removed the late fees. I was assured that the monthly automatic payment was the minimum payment and I wouldn't have this issue again and that it would not have reflected late on my credit report. Several months later I get another notification that the account is past due. I call again in XXXX and again find out that the same thing had happened again - the automatic payment was coming out, but not the amount that needed to me. I again explained the situation and it was again addressed by customer service and everything was taken care of. I specifically asked if I could have a written notice that the automatic payment was updated and I was told it would be reflected online. Now this month i went to get pre approval for a mortgage and found out that the account was showing two months behind on my credit report and did show late the previous times also! I called customer service and spoke to them and they again showed that the automatic payment that supposedly been adjusted the previous two calls had not been changed and it still wasn't enough for the minimum payment. I asked to have the issue taken care of and the rep told me he wasn't able to and opened a case on it. I paid the amount and made the account current and cancelled the automatic payment having to now call in to pay the payment monthly to make sure this doesn't happen again. At this time the errors and not changing the automatic payments have negatively impacted me on my credit report and I was just charged several late fees for this last bout of late payments - even though they shouldn't have been. 

The above is a statement of the overall issue I have had. This information was submitted to the XXXX XXXX XXXX after several attempted phone calls to American Express did not resolve the issue - I was only ever told, an investigation has been opened. 

On XX/XX/XXXX, I received a letter regarding my complaint to the XXXX XXXX XXXX. The letter mirrored my above statement about the issues with the automatic payment not being the minimum payment that it should have been. In the letter American Express states : " On your correspondence you mentioned that you spoke to us on two occasions to update the Autopay from a fixed amount to the minimum due payment. We were unable to locate the calls referenced in your correspondence. '' I find it convenient that the calls that would substantiate my claim " were unable to be located ''. 

To add to this since making these complaints it seems as though American Express is now trying to intentionally make my credit report worse than it was before I began making the complaints. In the last month American Express has updated it's reporting of my account, changing that was reported late and when. As of pulling my credit reports today two of the three credit reporting agencies are showing something different being reported by American Express. How in making a complaint did my payment history get worse? 

If I am able I will gladly provide these reports to show that American Express has been consistently changing my report ( for the negative ) since complaining, and also the phone statements with the dates, times and lengths of the calls to American Express to have the payment history updated.