@Zazie
When I was a heavier drinker, I would lose my keys, phone etc. and find them in the strangest places. Check the fridge/freezer, maybe in the oven, or somewhere in the fish tank. Do you have a mischevious cat? I find that they love keys.My keys were lost for over 6 months. I looked everywhere or so I thought. One day when I was rummaging in the pet stuff, I found them. Must have dropped them when my hands were full. So I would suggest looking in every unlikely place, under sofas, beds etc.