Solution: There may be no users in the dropdown, you have to type out the name of the user you want instead.
Original Issue: Afternoon, so here is my issue. I am an admin over a service desk project which I didn't create but was able to create some automation rules in. We then decided to create a secondary service desk project. I made that project but cannot create automation rules in it.
Error is: Selected user has been deleted, and there are no users in the drop down.

I appear to have the same permissions in both projects but I must be missing something somewhere. Ideas?
Thanks!
Jason