FTP FileZilla connection issue "Connection refused by server"

Question

I'm trying to set up file transfer via FileZilla and it doesn't seem to matter what details I put in, I always get the following error:

Status: Connection attempt failed with "ECONNREFUSED - Connection refused by server". Error: Could not connect to server

My Dad has tried on his computer (with FileZilla on Windows) and it connects and everything is fine.. When I try on mine with all the same details that he put in, it comes up with that error.

I read that a firewall might be blocking it so I double checked and my firewall through system preferences and it is off.

Anybody know why this might be???

Additional info:

Macbook Pro running OS X El Capitan version 10.11.6

FileZilla version 3.23.0.2