Sony Xperia - Hard Reset / Password Removal
Step 1 — Xperia Play - Hard Reset / Password Removal
Open the Emergency call keyboard.
Enter this code: *#*#7378423#*#*
From the Service Menu select: "Customization Settings".
EditStep 2
Select "Reset customization" and "Reset customization and reboot".
The Android system will erase all personal information and will reboot the phone to the original factory settings.
EditStep 3
Did you do it successfully?
Courtesy from iFixit (https://www.ifixit.com/Guide/Xperia+Play+-+Hard+Reset+-+Password+Removal/30567)