This is a bug on mobile devices. If you can get to a laptop or desktop, you can move your files into another read-only folder.
See this "How To" from James
If a student is posting too much, you can control their ability to post.
Click “Manage Teams” and check the box to mute student.
I have students who are no longer in my class, but still in Teams. Also, how can I change their status to guest?
There is no difference between student accounts or guest accounts in Teams, so don’t change the role to guests.
If you want to remove students from a class in your Teams: Select “Manage Team” and click “X” to remove student from the list.
if you remove a student who has submitted work for grading and the work has been graded, their name is no longer visible in the team.
Their name will also NOT appear in the grades tab.
Select your teams and click in “manage teams” under “…”. Then you can find all the log information from “Analytics” tab.
Make sure to convert the video to a small size so everyone can see it faster. Not everyone has a high-speed internet connection.
For short videos, say 30 seconds, it really should be less than 10 mb. Longer videos could be up to 50 mb. Shoot for small sizes of 10 to 50 mb. Make sure they save in .mp4 format
You can find a How To to compress large videos below.
You can draw on the page but you cannot edit the text in a PDF. PDFs cannot be modified or collaborative edited. Files and app types which support direct editing, as well as collaborative editing include: Powerpoint, Word, Sway and Forms
Note: the original idea and screenshot is provide by Lindsey Devillier from Beijing World Youth Academy. Thanks for sharing