How to unlock an iphone 5s version?

I found an iphone 5s but it's been lost for a few days (many missed calls) and there's no really no point turining it in. By now I'm sure the owner has bought a new one with their insurance.

Or… You could do the honest thing, and check to see if the owner is still looking for it, and return it to them.

Yea there's still the point of turning it in. If anything try calling that missed call's number & inform them.

No point anyway since the activation lock would prevent you from using it if you tried to reset it to use as your own.

Correctly would probably have to find the owner and call one of the phone numbers from there to get to him, maybe will even get a reward. If you decide to keep it, the owner probably has an activation lock that will make the phone useless and also probably called his network and declared it as lost so is blacklisted, and will not work in your country.