Hi all, I just spent 1 hour on the line with an AT&T rep and this is what resolved my issue.
We disconnected from my normal wifi and connected to my hotspot on my phone. Once I did this, I was able to sign in and see my email. At that point I could then switch back to my normal wifi.
The rep said this is something that they are working on and it is a known issue but switching wifi, at least for my case, helped me to get into my email. Hope this helps others. I told her there were many having this issue and she asked me to put this workaround out to you.