Backup Your Device data
Method 1:
1. Now Turn On Your Device.
2. Go To Home Now Select Menu
3. Than Select Privacy -
4. select Factory data reset Reset
5. select this Erase everything.
Wait Few Second Device will be auto restart and solve your problem.
Method 2 :
This method Batter For Remove Pattern Lock. If You Forget Pattern lock Try this method.
1. Turn Off Your Device. remove battery and insert again.
2. Press and Hold Volume Up + Power Key Until Appear Logo On Screen
3. when Show Recovery menu chose this option Use Volume Down key
> wipe data/factory reset Press Power Key To Confirm.
4. now Select Yes -- Delete all user Data confirm use power key

5. after finish Reset Select Reboot System Now

wait few Second System will be auto restart.