Edge has some weirdness going.
Last week I went to visit a friend of my late wife to help her (the friend) upload a book to Amazon KDP. We started out using her husband's new Windows 11 laptop, with Edge as the browser. We kept getting a security warning that wouldn't allow me to get into the KDP site.
I gave up. I didn't know what they had for a computer so I had brought my own laptop, running Windows 10 and Firefox. With Firefox we encountered no problems, and the book was uploaded and is now on sale.