I want to know if it is possible to get Canvas to automatically mark an assignment as "missing" after the due date and/or last available date for the assignment has passed. This seems to happen for assignments where, for example, the student has to upload a file. If they haven't done so by the due date, it gets flagged as missing. But when I give assignments based on an external LTI, nothing happens after the due date. Is there something I can change?