OK, I figured it out! I had this issue with MANY sites, and I use Fire FTP in case your wondering:
I recently reset all my passwords for LookStat to use.... well, after reverting to the old passwords, I can now log into the FTP. WEIRD!!! Its almost like a few agencies didn't update my FTP credentials or something like that (not really sure what happened) it seems.... very annoying. If you plan to use LookStat or any other uploading services, keep this one in mind! Almost seems like some kind of a sync issue between site log in and ftp login, I really have NO idea.
I had issues with Big Stock Photo, and Stockxpert FTPs.... I'll post more problem agencies if I find them.