The Enter Verification Code gives a 404 - page not found error on mobile (I was using iphone) so I had to use computer to create the link.
Battle.net server is misconfigured. When you enter the Enter Verification Code in your browser, it will connect to https://www.blizzard.com/link where your link doesn’t have the “www” prefix. That’s the only difference in the links. So their link server is not handled by the one that uses the www prefix.
These companies need to stop selling these products as something they are not that is absolute fraud. Live service games are trash. It’s nothing but a Ponzi scheme, especially when these products are being sold under our perpetual license. You should never need Internet to play a video game unless it’s being sold to you under a subscription.