If you're using the built-in Hype buttons, there's no notion of "active", only normal, hover, and pressed. After being pressed the button will go back to the normal or hover state (depending on where the mouse is at!).
If you want a notion of an active state, then you'll want to trigger and play a timeline that animates the button to a different state. (And you may want to use this method for other states, as the button behaviors will override anything set by this).