Can't Leave Comments for a course

I received a link for my colleague's course so I could leave comments. However, the comment box isn't showing for me. He confirmed that the comment box is enabled. When I review the tutorials, it shows the comment box to the right of resources, but I'm not seeing it. I'm sure it's something super simple that I'm missing, but I can't figure it out. If you need the course link, let me know. Thank you.