How to unlock a lost iPhone 6 phone?

My brother found an iPhone 6 under his car and its says the phone is lost and too call the number we did that and no one anserws we left voicemails no one has called back its been two months and it feels like a waste to not use any ideas on how to unlock it if its a lost phone?

Nothing you can do, the owner has it icloud locked.

What do you mean locked? If it's asking for the owner's iCloud account, then there's no way. No matter how much you beg, it's impossible to fully bypass the iCloud lock. If it just has a Passcode lock, then you just put the iPhone in DFU mode and restore it in iTunes.

Anyways, you may be in possession of a stolen phone, which could possibly land you in jail/fees.