How to unlock an iphone with a pin number?

Ok, i found yes found an iphone in the woods 1 week ago. The owner is quite upset but has not contacted me despite exhaustive methods to return it to the rightful owner. I can't open the phone to try and get their contact number as it has a pin lock code. I tried plenty of times to guess it and each time it blocks me out for longer. I'm now up to 15 mins and don't know what next. Is there any way i can bypass this code to find the owners name and number which will most likely be in the phone?

Hopefully not, but you can restore the phone, and sell it on eBay

You can't bypas the code.

You can't unlock the phone with a pin number,
you could sell it ebay