You will need
Make a call customer service from another phone.
Tell the operator about your problem and what are the approximate password that was or is a secret code that you entered for the first time.
If the secret code has failed to use it himself when the phone is switched on, it is necessary to call the operator and additional information (date of trip, reason, some data from the phone).
After that, wait for a clear plan of action from the operator, who will help you with your new password.
Do not give your details to anyone unless you don't want someone changed your password and used a secret code.
Now there is a special program on the Internet, which downloading can be much faster to solve the problem with unlocking the phone if forgot password.