OK, perhaps you can provide some more examples then?
Also, what does the SYST command return?
(Probably need to use "quote SYST" to send the command interactively)
Likewise the output of the STAT command would be useful, and the banner details, for example as shown in the line prefixed with 220 below:
$ ftp -A ftp.mirrorservice.org
Connected to ftp.mirrorservice.org.
220 UK Mirror Service FTP server version 1.4 ready
ftp> quote SYST
215 UNIX Type: L8
ftp> quote STAT
211- maxwell-if-a.mirrorservice.org FTP server status:
211- Caching FTP server Version 1.4
211- Connected to n.n.n.n
211- Logged in anonymously
211- TYPE: ASCII, FORM: Nonprint; STRUcture: File; transfer MODE: Stream
211 No data connection