5.1 When setting the department leader or assignee, no one can be found in options?

The department leader or assignee must be a member directly under the department. If your target member cannot be found, it indicates that the member is not directly under the department. 

For example, in the following figure, member Lucy is directly under HR and is not a member directly under the HR & Admn, so there is no option for memberLucy when setting the department leader of the HR & Admn.

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You can uncheck the "Show members of sub-departments" to browse the members directly under a department in the Organization Structure page.

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