The only way to gain access to your phone is through the hard reset operation. Turn off the phone then press Volume Up + Power Button until the Android logo appears. Select Wipe data/Factory Reset and wait for the process to complete. Once completed, select reboot phone and wait. You might need to reconfigure the phone from scratch because the content was deleted. This means that the accounts, settings, and apps were deleted. You will, however, gain access to the phone.
