Your combination switch, is your indicator stalk, headlight switch, and I think windscreen wipers too.
It is attached around your steering column, and I think you may have to remove the steering wheel to dissemble it.
If you do pull it to bits, careful of losing springs, tiny ball bearings, and loose contacts, also take note where and how contacts fit when dismantling.
If you clean it up, it has some sort of lubricant on the contacts,which should also be replaced.
Good luck.
A.