My American Express downloads are no longer balancing

Topdock

This is a recent problem. I have been using Quicken to track AmEx credit card since 2012. It has always been in balance until this past week. It is now off several thousand dollars when I try to reconcile.
A quick check shows at least one payment to Am Ex that has a message that says this was entered manually and does not correspond to a download. This was an entry for November 2021.
I ran the download several days in a row with no resolution.
I ran the validate and repair function and it shows no errors in my backup file.

Sherlock

To determine what has changed, I suggest you compare the running balance of the account register in the current Quicken file with the running balance of the account register from a Quicken file backup saved when the account was last reconciled.  One way to accomplish this is to print the registers to text files.