Sign in Problem with this site

[mmtscn]

This is on Chrome.

When I try to login at https://community.canvaslms.com

It sends me to: https://www.instructure.com/canvas/login/free-for-teacher

I logged in to my account. It brings me to my courses admin page. That's fine. But when I click "help" → "Ask the community" link. It sends me to: https://community.canvaslms.com/t5/Question-Forum/bd-p/questions

And my status is still not logged in.

So I repeat the cycle by clicking "Sign In". It goes on. I'm still not logged in.

This time, I got logged in on Firefox. But I remember I had the same issue on Firefox before.

What is the cause and how to fix it?

Thanks!