Get hot soapy water and scrub it. But not hard srubin in circles.
Well here's a way to fix that stain . Call your local Carpet place, and ask what type of remover they have and read the Directions on the back of the bottle . If it's stuck on top of the carpet trim with a pair of scissors.
Mix vinigar lemon juice and cream of tartar and apply to object an scrub in a circular motion