I recently set an assignment to auto assign peer reviews. For some reason 2-3 students were not assigned peer reviews, even though they submitted assignments of their own. In addition, two students were assigned to peer review students who did not submit assignments.
I've had to go in and manually fix this issue after started to grade the assignment and I noticed that a few students have not submitted their peer reviews. This means I have to extend due dates for peer reviews for a few students at the end of the semester when we are all overwhelmingly busy, and I'm not even sure they are going to check their assignment comments again. I selected the auto assign feature to save me time and headaches, but it's actually created more.
How can I be sure this does not happen next time I do student reviews on an assignment, aside from simply engaging in the hassle of going in and doing it by hand to begin with?
That does sound very odd. For the 2-3 students that were not assigned peer reviews after adding their assignment submissions, did they submit after the due date by chance? According to How do I automatically assign peer reviews for an assignment?, "If a student has not submitted the assignment or submits the assignment after the due date, the student will not automatically be assigned a peer review and you must manually assign one." If that's not applicable, how long after submitting, did they check to see if they were assigned a peer review? It can "take up to one hour for Canvas to assign peer reviews."
As for your two students receiving peer review assignments when they hadn't submitted anything, I'm not aware of anything that would cause that to happen automatically. I'd recommend reaching out to Canvas Support for further assistance. They can look at your specific Canvas instance to investigate why those two were assigned peer reviews.