Only managed in-house apps and App Store apps can be distributed to devices enrolled using User Enrollment. App Store apps must be assigned to users' Managed Apple IDs (user-based assignment) before distributing them to devices. For more information, see the following pages in the Jamf School Documentation:
It is recommended that you distribute managed apps using the automatic installation method to devices enrolled with User Enrollment. You can distribute apps to devices individually, or use the previously created smart device group to distribute the apps to all devices enrolled using User Enrollment.