Assign iOS Devices to manually created users during enrollment

[Andreas_Schenk]

I have a JSS that has no LDAP Server available.
When doing a user initiated enrollment for iOS, the assign to user is not available to manually created users (from another installation that has LDAP Servers, I know it works for LDAP based users).
It seems that manually created users won't work for the user initiated enrollment.

Or is there something I am missing?