Error when editing a listing

I am getting an error message "An error occurred when we tried to process your request. We apologise for the inconvenience." when I submit my changes to my listing in UK, Germany, Italy, France, Spain, Netherlands marketplaces. This error persists for 2 months already.

I can add / edit listing with flat file without any issues.

I've contacted support multiple times and tried all their suggestions (listed below) and it still doesn't work:

a. Clear the cache, cookies, and history within the internet browser the seller is using.

• Clearing the browser's cache can force recently changed web pages to show up properly.

• Each browser handles caching differently; the correct steps for the particular browser must be followed.

○ Cache

○ Cookies

○ History

•You can also try holding Ctrl+F5 on their keyboard to hard-refresh the page.

b. Log out of Amazon completely, including buyer accounts, and close the browser.

c. Use an alternate browser. Mozilla Firefox is the preferred browser for Seller Central. I've tried: Chrome 125.0.6422.142, Safari: Version 17.5 (19618.2.12.11.6), Firefox: 126.0.1

d. Verify whether McAfee or another antivirus software is running on their computer, and confirm that no anti virus software is running. I understand that I might be required to update the antivirus settings to allow Amazon.com cookies and access.

e. Used a different computer with different operating system (Windows and Mac)

Can you please investigate? @Winston_Amazon