To unlock your Concord ZTE768 mobiles pattern lock, please  try these steps below:
I have write 3 method below –
ZTE Origin hard reset Master Clear/Reset Cricket Origin reset ZTE V768 ,

Method  1
1. Make sure your phone has been powered off.
2. Hold down Volume up key and press Power key at same time until the screen lights up.
3. Press Home Key to access Android System Recovery screen.
4. Press Volume up\down key to locate wipe data/factory reset, then press Menu key to access factory data reset menu.
5. Select Yes-delete all user data, then press Menu key to confirm wiping data from the phone.
6. When finished, select reboot system now, then press Menu key to restart your phone.
Every data will be erased!

or You can reset your ZTE device’s password:

Method  2

Turn off your phone, then turn it on.
Select emergency dial. Input *983*987# in emergency dial-up pad.
It will restore factory settings and your personal data will be erased.

or from the menu
Method  3

Privacy: Reset to Factory Settings

1. Touch the Home Key > Apps icon > Settings > Privacy > Factory data reset > Reset phone.
2. Enter six zeros on the screen and touch Erase everything.

WARNING! All your personal information and downloaded applications on your phone will be erased after the factory reset. ZTE Origin V768 Phone Password A password can protect your phone and help prevent unauthorized use. When the phone is password protected, it will ask for the password every time the phone is turned on. Password protection is disabled by default, and the default password is 000000 (six zeros).

Thanks