Help! My Buttons! My Buttons!

Remove the button. Carefully use a needlenose pliers to squeeze the two tines of the metal fork so that they'll more securely grip the button. Reinstall the button. Take the opportunity to apply a good brand (CRC) of spray silicone lube to the button box—get behind the dashboard and spray all pivot and slide points in, behind, and beside the box, operating the buttons and park lever to make sure the spray gets everywhere.

Check the Neutral button for looseness, too; it gets a lot of pull-action (every time you put it in Park).