Came to this topic by googling this issue.
Few days ago I bough this game in a computer shop for Xbox (Xbox Series X).
I'm experiencing exactly the same issue as the other users. I'm gaming on a 4K TV and I succeeded to open that login page (Connect me now) only when I connected to my Xbox remotely. So I believe it could be related to rendering screen resolution (my laptop has FullHD resolution). I've typed in the credentials but nothing happens.
I'm attaching the screenshot. The second time I tried to open the login page doesn't work.
Please let me know what other technical info should I provide to solve this issue fast.

I just bought Assassin's Creed: Valhalla for my Xbox Series X and there's a problem trying to sign in on the Ubisoft Connect.

This Ubisoft Connect prevents me from playing the game and it's not working for hours.

In the start of AC: Valhalla you need to press A "Connect Me Now!". It will make a sound knowing the button works. However, the "Connect Me Now!" Sign in or create account page will not load successfully and it will take you back to the Ubisoft Connect page where it says "Connect Me Now!"