Register for an Event Someone Else

Hello!

I'm trying to register and existing Contact using Rise, but I don't see the button that it should exist according to this document [https://docs.imis.com/20.2/Understanding_iMIS_Features/Events/Registering_for_events.htm?Highlight=register%20for%20events] and that would let me select another contact:

I'm logged in as administrator, so I guess it's not a permission problem.

Thank you