Using the "Message students who..." keeps going to the wrong students

Community Member

So I've been trying to use the "Message students who..." feature in the gradebook. I usually set it to message students who scored less than 50%. I only do this after I've checked and updated any grades for that assignment for the class. However, I had students from another class who got the message and were upset. They had turned in their work but I hadn't entered grades for their class yet. 

Now I do have all my classes linked, but in the gradebook I had chosen just the section I wanted to send messages too. I looked a the names that popped up and removed any names I didn't want to send a message to. There were no names on that list of students from other sections. I hit "send." Then this morning students from a completely different section got the message and lost their minds. What am I doing wrong?