FTP too many connections - None listed in cPanel

Hello, I'm trying to upload 6 files to my web host, and after the third I get "Response: 421 Too many connections (8) from this IP". So I login to cPanel, click on "FTP connections" and there are none; "There are no active FTP connections for your account.". Reload does nothing, it stays empty. I know it's not a problem with FileZilla as it's set to upload a single file at a time and I don't have issues uploading to my own FTP server at work (albeit probably has much less severe restrictions). Before I contact my web host, I'd like to: 1. Understand what's going on (is this a CP bug? Is something out of sync in the configs? etc..) 2. Make sure it's not something I can address myself through cPanel. Any idea what's going on? Thanks