[RESOLVED] ComboBox Problem

I have a combo box in a registration new staff/Admin. I have it in tab. Tab 1 is for admin which is solve since i'm only using text box. Bu I have problem with the staff part. For staff I need to drag the id from a table in database. I tried to use DataEnviroment connection, but its only show 1 data from the database. Is there any setting I need to change?

Thank you in advance.