[galaxy-user] FTP Upload Error

I'm having trouble uploading via FTP to my Galaxy account. I've been receiving the following error message: 503 Sorry, the maximum number of clients(3) for this user are already connected. I've ensured that I'm only using a single connection to upload. Any clue what's going on? I still have available space in my Galaxy account for the upload and I've previously uploaded similarly sized files with no problems.