Found iphone and reseted it?

I found an iphone 5c, i've reseted it to its factory version, but i'm pretty sure the phone was already reported lost or stolen, now that thats happen, what can i do i want to sell it but doesn't seem like its going to be valuable now

Return

You can't sell lost/stolen items & it can be tracked as well.

Take the phone to the carrier that shows when you turn it on or an Apple store. They can use the ESN or IMEI, to return it to the owner in less than a day, if the owner is local.

Since you stole it, your best bet is to turn it in to the police.