Is there any way to only have in your to do list the marking for only the sections you teach as opposed to having everyone on every courses marking in your to do list?
It sounds like your section is cross-listed with sections belonging to other instructors. In my experience-based opinion, this is not a good practice. I suggest that you speak with your school's Canvas admins to ask "why" and see how this can be undone. (At least in the future; de-cross-listing mid-semester can wreak havoc on submissions and grades.)
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