I dont have the option to "Play a Sound" when I try to find my other iPhone

When I try to use "Find My iPhone," both of my phones (Phone A and B) are listed in "People", but Phone A has a "Play a Sound" button for Phone B, but on Phone B there is no "Play a Sound" button for Phone A, only a "Contact" button. I can see where they are on either phone.

How do I get the "Play a Sound" button on Phone B so I can ping Phone A?