cannot create folder or copy files to external hard drive
I have a 2TB SSD connected to my Mac Mini M1 via USB port. I was able to copy files to the drive before but now it seems that when I copy a file to it or create a folder on it...about 10 seconds later it just disappears. I'm using Big Sur 11.2.3. Why is this happening now ? Is it iCloud Drive ? I've try to deactivate that...same thing. The SSD has 1.62 TB available of space (so it's not a space issue). Help ! This is serious and I need to get work done.