Student markup a pdf document

[MelissaLuffman]

My students are using Canvas on iPads.  I uploaded a document for students to annotate.  This is not through the student annotation feature.  When student went back to continue working on the assignment, all the student's work is gone. Is there a way to get the student work back?

[greydon]

Hello @MelissaLuffman 

The assignment wasn't a student annotation type of submission? Were the students just downloading the file, marking it on their own devices, and then uploading it directly? Did you make edits to the assignment by chance? Change due dates or anything similar? The work should not have just disappeared.

Because of the complexity of the issue, and the concerns for privacy, it would be best if you contacted Canvas Support directly to pinpoint the source of the issue and provide a resolution: 

https://community.canvaslms.com/t5/Canvas-Basics-Guide/How-do-I-contact-Canvas-Support/ta-p/389767