Bury it in uncooked rice and leave it in an airing cupboard for a few days, although I suspect that you'll need to get inside it to check whether there is any corrosion on the contacts of the switch - Not always easy with the rubber push-button switches (which is what I suspect this has).
Water inside the lens now won’t switch on. Dried it out - still nothing. Is it saveable? I don’t want to throw away
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