SDOD creating Department Heads

SDOD creating Department Heads

I have created Departments to represent various buildings on campus.  I am trying to assign Department Heads.  The names of the Department Head is in the Requester list.
However, when I try to assign a name to the Department the name list is blank.  
I type in the first few letters (I have even typed the entire name) and the list is coming up blank.

How do I create Department Heads? 

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