Snow foam mark on MG4 plastic panel

[Tig170]

Cillit Bang Limescale and Grime?

Personally I'd start with something more gentle, e.g. a small bit of washing up liquid (on a damp cloth) in a small corner, if that doesn't work then try bathroon clearner which is plastic safe.

.... if that doesn't work then call the manufacture hotline of the foam cleaner, who should be able to advise.