MyCloud EX2 Ultra FTP Remote Access

Hi everyone. My name is Nick, nice to meet you. This is my first thread here because I’m having a lot of issues about configuring EX2 Ultra by accessing remotely through FTP. I’ve followed every guideline and thread posted here and on WD website (also including User Manual) but I’m not able to make FTP working.
First of all, I surfed 192.168.1.1 page, in order to reach my router config page; then, I opened port 21 (w/ TCP protocol) for MyCloud EX2 Ultra. I’ve activated UPnP feature on router too.
So, that’s what I’ve done, once gone on WD local config page (in my case 192.168.1.2 address):

  1. Sharing Tab: once located the folder I want to access with FTP, I’ve set ON on FTP Access Feature (Anonymous - None permissions)
  2. Settings Tab > Network:
    IPv4 Network: DHCP
    IPv6 Network: OFF
    FTP ACCESS: ON Configured as follows:
    Maximum users: 10
    Idle Time: 10 min
    Port: 21
    Control flow: no limit
    Passive mode: Default
    External IP in PASV mode: ON and then I pressed on Get IP
    Client Language: Unicode 8bit
    TLS: Explicit ON
    FXP: OFF
    AFP Service: OFF
    NFS Service: OFF
    WebDAV Service: OFF
    SNMP: OFF
    SSH: ON
    Dynamic DNS: OFF
    Remote Server: ON
    PORT FORWARDING: FTP Service (w/ TCP Protocol); external port 21; internal port 21; test NOT SUCCESS.

When I try to connect through FTP from outside of my LAN, I can’t reach MyCloud. I’ve tried both FileZilla and ftptest.net and these are the errors I get:

FILEZILLA:

Command: MLSD
Error: Connection Timed Out

FTPTEST.NET

Error: Carriage return without line feed received
The replies sent by your server are violating the FTP specifications.
You have to upgrade to a proper server.

I’m able to ping my LAN from outside, but I can’t access server. In addition, on the router page, Firewall is disabled.
Does anyone knows how can I solve this issues? Thanks a lot in advance.
Greetings
Nick