Google Assignments LTI 1.3 - Some students cannot access doc

[lgleaming]

Hello -

I created a Google Assignment using the external tool. Some students cannot see the assignment. When they try to access it, it states it as "Unknown Drive File" and File missing. There is an option to "Get a new copy" but they are telling me it does nothing. 

I have had many kids access the doc and submit it without issue. Just within the last hour I have had 3 students contact me with this problem.

Anyone know how to resolve this issue?

Thank you.

[winnie_milner]

This was just reported to me today. One of my English teachers had this happen in her AP class. Two of her students had been working all quarter on compiling a Slide Deck through Google as an External Tool submission type and after weeks of using the file, their work was gone. The files are not in the teacher's Drive nor the students' Drives.  It says "Unknown Drive File" when they go to open the assignment.  Is there any way you know of that can help to retrieve these files AND keep it from happening to other students?