No free space message

Hi everyone, I’m getting a no free space message, as I try to move a 256GB file onto my Drobo that says it has 890GB free. Any suggestions?
Best, Brenda

Run a filesystem check from the attached PC - it’s likely there is free space marked as used by the filesystem.

I’m on a Mac, not a PC.

What size are you formatted to? (2TB, 4TB…16TB)

By PC I mean personal computer, whatever OS it’s running.

how is it formatted? as in what file system, perhaps there is an issue with having a single file that big (i’ve never had a file more than 50GB).

I know that if you tried to put files bigger than 4GB onto a FAT32 formatted disk it gave “out of space” as the reason for not being able to do it, even though it actually meant “the file system doesnt support files that big”