For cleaning plastics with a textured finish, I have had some success with some good old fashioned methods; a mix of detergent (washing up liquid), bleach (Domestos) in warm water. Apply with a small scrubbing brush such as a nail brush and rub well in. Finish by wiping with a damp cloth.
Apply a polish of your choice when the surface is dry.
Takes a bit of time, patience and some "elbow grease".
Be aware that solvent based cleaners can damage the surface of many plastics which is why I would go down the route of using such household cleaners as washing up liquid and bleach. Citric acid based cleaners, those smelling of orange peel should also be safe on plastics but I would advise that you test on a small patch first.