APEX Dynamic Actions

I am a new APEX user, and I'm having a problem with Dynamic Actions. 

I have a page for users to enter a contact name.  I need to display the contacts phone number in a display only field from the per.per_phones tables.  I essentially copied the 'Creating a Set Value Dynamic Action With a SQL Statement' from the 'Building Dynamic Actions in Oracle Application Express 4.0' OBE.  It is supposed to set and display the phone number item whenever the contact is changed.  This is not happening.  The phone number item remains blank until I reenter the page in edit mode.