FileZilla says Disk Full. But it isn't.

[DanL]

I have a Hostgator account that I'm connecting to with FileZilla. It has worked flawlessly for years. All of sudden, when I try to upload a 84KB file to my domain there, I get
Status: Logged in
Status: Retrieving directory listing...
Status: Directory listing of "/" successful
Status: Resolving address of xxxxxx
Status: Connecting to 108.xxxxxx...
Status: Connection established, waiting for welcome message...
Status: Initializing TLS...
Status: TLS connection established.
Status: Logged in
Status: Starting upload of /Users/xxxxxx
Command: CWD /xxxxxx
Response: 250 OK. Current directory is /xxxxxx
Command: TYPE A
Response: 200 TYPE is now ASCII
Command: PASV
Response: 227 Entering Passive Mode (108,xxxxx)
Command: STOR xxxx
Response: 552 Disk full - please upload later
Error: Critical file transfer error

Won't let me do it, because it says the disk is full. But it isn't. Using cPanel, I can easily upload to my Hostgator account, and my account listed as being only 88% full.
So why is FileZilla teling me that my disk is full when it is not? Hostgator support confirms that I am not over my storage limit there. What exactly does error 552 mean?

[botg]

The message is coming from the server. The server thinks the disk is full. If your hosting provider cannot figure this out, you should switch to a better hosting provider.

[DanL]

Thanks. That's why I specifically asked Hostgator support if my disk was full. They said it wasn't. So I guess they have a problem telling apps that it is full when it is not. As I said, curiously, I can upload easily with their cPanel. But FileZilla, at least now, is screwed.

[boco]

Looks like the FTP server software doesn't correctly sync or calculate the limit (which is not a actually disk limit but just an arbitrary quota value). But yes, they are in full charge to fix this, as it is 100% on their side.