What should you do if you can't find a contact lens in your eye?

My brother thinks the contact lens in one of his eyes is "lost" and not in its proper position. Him, my mom, and me have tried for about an hour to find it and haven't been able to do so. Honestly, we don't even know if it's actually still in the eye. Anyway, it's already midnight so we can't head to an eye doctor at this hour. Assuming the lens is in fact still in his eye, would it be bad if he slept with it overnight this once and then headed to the eye doctor tomorrow morning? We've tried eyedrops to try to bring it forward, but nada. Are there other tips you might give? And if not, would one night be so bad? Urgent:T

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