I FOUND A CELL PHONE

Question

I FOUND A CELL PHONE MODEL 8100 AND IT HAS BEEN LOCKED OUT AND I NEED THE CODE. I CONTACTED T-MOBILE TO SEARCH FOR THE OWNER. THEY DID NOT HAVE THE PURCHASER ON RECORD. I SEE THAT THERE ARE SERVICES WHICH CHARGE TO HAVE THIS SERVICE DONE. I TRIED THE HONEST APPROACH BY TRYING TO RETURN THE PHONE WITH NO SUSCESS. IS THERE A WAY TO UNLOCK THIS PHONE SO AS TO USE ITS FEATURE.