First thing would be to check if you've not accidentally got your own IP banned. Search if your own IP isn't listed in fail2ban. Secondly make sure the new Port is also allowed by the Plesk firewall and (if applicable) your providers firewall.
I checked all of those but i couldn't find any banned or blocked IP, my Server simply denies the access to root.. Even if i try to login through ftp...
I can only access through administrator wich doesn't have as many rights..