You have ftp site named ftp.

Do the following steps as:

1.vi /etc/vsftpd/vsftpd.conf

anon_upload_enable=yes

chown_uploads=yes

chown_username=username

2.service vsftpd start| restart

3.directory owner should be ftp user: chown ftp directory path allowedto upload files.

4.Write permission should be set to owner user.

By default anonymous user can only download files from the ftp. Should write anon_upload_enable=yes to enable anonymous upload files. Default Directory for anonymous is /var/ftp.