NotePerformer mixer showing instruments not in score

Why are there instruments int he NotePerformer mixer showing that are not used in the score? Can this be the reason that some instruments are not playing or playing with the wrong sound? Reseting the mixer panel doesn’t help.

Have you added and removed instruments from the original score? If so then Dorico won’t remove allocated channels until you do Apply Template again.

Thanks Paul, that fixed it.