Background: My university requires students to attend two events on campus per semester, and we use Canvas to track their attendance. Each event is an "assignment" worth 1 point, and if they attend, we give them that point.
I'd like to message just the students who attended a particular event with a link to a follow-up survey--that is, I'd like to message all the students who scored a 1 for a particular assignment. To do so, I'm using Gradebook's "message students who" function. In the dropdown, I select that I want to message students who "scored more than" and then I type a 0 or a 0.5 in the box. Both of these selections seem to do the trick: the field of addressees is instantly filled with the long list of all the students who scored a 1 (meaning they attended the event).
My problem: When I try to send the message, I get the vague error "recipients invalid" and can't send the message. I don't know if this is a problem with my "scored more than 0" selection, if I'm trying to send the message to too many students, or if there are individual problems with the emails or accounts of some of the students I've selected--or if it's something else entirely. Searching for similar problems hasn't yielded an answer, nor has reading online guides.
I'd welcome suggestions that will fix this "message students who" problem or that could offer another way for me to message a large group of students who all scored a 1 on a 1-point assignment.