Accessing and using Microsoft Teams on smartphones and tablets across platforms
Hi Woo-Jin Lee,
I'm sorry that you are experiencing this issue, and I will try my best to assist you.
It seems like the problem you're experiencing with the "Drop Your Files Here" box disappearing when you try to drag and drop files in Teams could be caused by a variety of factors.
One possibility is that there might be an issue with your Teams app that is preventing the drag-and-drop functionality from working properly. You could try clearing your Teams app cache and cookies by following the below steps
If Teams is still running, right-click the Teams icon in the dock, and then select Quit, or press Command (⌘)-Q.
In the Finder, open the /Applications/Utilities folder, and then double-click Terminal.
Enter the following command, and then press Return:
rm -r ~/Library/Application/Support/Microsoft/Teams
Restart Teams and check it is working. If the issue persists, please try to uninstall and reinstall the Teams app
I hope it will be fixed. Please let me know if you still need further assistance.
Greetings
Jade - MSFT | Microsoft Community Support Specialist