Emails delivering to one user but not another

Emails delivering to one user but not another

I've just moved my dns to bluehost and gone through all of the setup, most of my email seems to deliver OK now however I have noticed that some, in particular, WeTransfer emails will only deliver to my admin user and not my secondary (which is the one I use most).  Any ideas why this might be?  I guess it's a setting somewhere but I'm pulling my hair out.

Thanks