factory reset. philips w337 phone

I can not access My philips w337 after i failed to enter the right patten to unlock the screen.I also forget my google account details like password etc...I have already tried the factory reset technique by pressing the vol up + power on button but yet its keeps saying system update....is there any more other buttons I should press together with the vol up + power button to activate it to the reset mode?.. Please kindly assist me on that.