EA says they are looking into "login issues across all of our games and services."
It appears, from tweets by EA Help, that the issue started with the Anthem game demo and got worse from there.
The issue is affecting the entire EA system.
You may even have trouble accessing EA Help, according to the Twitter account:
While we're working on the login issues, you may also have trouble logging in to EA Help. We're doing some work in the background and will be back online as soon as we can.— EA Help (@EAHelp) January 25, 2019
We're now also looking into login issues across all of our games and services, including the #AnthemGame demo. Hang tight--we're on it, and we'll share more info as we have it.— EA Help (@EAHelp) January 25, 2019
We're looking into the infinite loading issue with the #AnthemGame demo. In the meantime, try relaunching the game and rejoining your mission to see if that helps you.— EA Help (@EAHelp) January 25, 2019
We're adding more server capacity to the #Anthem demo right now. Hang tight while we work to get everyone into the game.— EA Help (@EAHelp) January 25, 2019