Cloning User Record Fails with Unknown Error

[sfscgjohnson]

Created LRP with following settings:

Component Title: User Record Clone
Clone button Label: Clone
Record name input label: User
Fields to be NOT cloned: None
Child Relations: PermissionSetAssignment, GroupMember, UserLIcense, ObjectPermissions,FieldPermissions
Template Record Id: Filled in with one of the records.
Clone child record name format: Cloned - [Child Record Name]

When running the clone it shows 30 fields excluded, 159 fields included.
When clicking on Clone it gives an error message....

Unknown Error.

Nothing happens / no record is cloned.
Any ideas?