Can't login with Win 11 PC, need help!

I'm trying to make some reservations but I can't login with 2 different PC here in italy (home & office, so 2 different networks and providers); login window doesn't come out
Try different browsers (chrome, edge, brave, vivaldi) also in incognito mode.

If I do the workflow of the room booking, when I put my email, it says "we found existing accoount, connect..." but button has same behaviour (infinite spinning and wait time)

The strange is that, if I use the mobile app (android) it works perfectly...