Class Average for Assignment is Pass Grade

I just got my grade back for a final assessment, and when I checked in Canvas, I saw that the average grade is 56.1%. I have never seen such a low average score for an assignment, and it counted for nearly half of our final grade. Would they not apply a grade curve in this instance? I am so confused. To me, it seems like we have been marked extremely harshly. I'm assuming lots of people in my class would be disappointed.. Who can I contact about this?