I have found a bug in ArcGIS On-line.
In settings on the feature layer, if you select ‘Keep track of who created and last updated features’ – then a newly created polygon will initially, correctly, give the user name of the person/use account who did the mapping.
But as soon as I view the polygon (logged in with my publisher account) – it says that I created the polygon, even if I have not edited it or updated it.
So all the polygons end up saying that the publisher account created them.
I have just un-ticked that option for now. But it would be good to have it working again.