Thank you @TheFaceProject
So, the game is actually my daughters but obviously I became completely obsessed!
On initial set up, I set it so no online play could happen (I didn't play at that point) but now I would like to play online.
I've done a lot of the work on her island and feel we've reached a bit of a peak and without online play, there isn't really much more to do.
Do I just turn off the parental controls to access online play?