Remote Access Assistance Please!

[markpainter 8]

Hi Folks.

Been running Emby on my Synology DS220+ nas for a couple of years now without any issues.
I have just moved my IP to a new one without a fixed IP address. 
Since then I have been having all kinds of remote access issues. 
I have set up a no-Ip account and set that as the DDNS server in the NAS and sometime it works ok.
But several of my family members are having problems connecting with EMBY connect - as am I at work. 
If I add the server manually ie http://*******.ddns.net I immediately get the "Unable to connect right now"  message as soon as press enter - it doesn't even try.
However on my phone it connects immediately - even though it's using the same wi-fi.
Is there a "Do this, Do that" to get it working. 
Incidentally, I have tried an alternative to Emby on the same NAS (Where I came from to Emby!) and it connects first time every time with their connect software. 
I REALLY don't want to go back there, but if I can't get this sorted, I may have to