Can you possibly sharea screenshot if what you do see? Is it just a blank white screen, or is there other content just not the student discussion posts? My normal advice in a situation like this would be to ensure both your web browser and operating system are up to date (could you tell us the version numbers of both, if you happen to know that, perhaps look at the Canvas supported browsers page for more info). Running older browsers or operating systems is known to cause blank white screens in some areas of Canvas, but I have not heard of it happening with discussions specifically.
I got local help from a help desk person at my school. Normally, I have enough students to put them into groups. I thought that this would be true this time around. It turned out that when I made the discussion a group discussion, there was no other team and I couldn't access it. When I unchecked the box for group discussion, I was able to enter the discussion and respond to students, my usual practice. I hated it when I had to be in group discussioins. If I knew enough to generate my own questions for others to answer, I didn't need the class, but the professor never showed up in a discussion. I think that's wrong. If the prof is going to be MIA, then he/she should tell Canvas to give each participant the same score. That's what I think. I refuse to be a faceless online grading machine. Anyway, thatnks for the suggestion.