How do you reset the phone lock on a samsung GT-S5230?

If you have forgotten or do not have the phone lock code then the only way around it is to perform a master reset. A master reset changes the phone settings back to the manufacturer default settings. This process will erase all downloaded settings, downloaded applications (graphics, wallpapers, ringtones, etc), and contacts. A master reset cannot be undone. Enter *2767*3855# from the standby screen. (You may need to remove the SIM before it will allow you to type the code in)