Ftp to public share from the command line

I am trying to upload files from a Linux machine on my network to a sub-directroy in the public share using LFTP. The bottom line is I want a script to upload all files of a specific type automatically.
I have ftp turned on for the public share. I have tried both with anonymous read/write ON and off.
I can upload files to the public directory without any problems using Filezilla, but with every terminal based client I have tried I get either:
Access failed: 553 Users may not upload files (/public/Uploadtest.txt) or connection refused

Anyone have any insight they could share with me?

Thank you,

John