On a Nokia phone press "Menu" and "Asterisk". The LCD display will show the message about disabling the lock.
On the phone of another brand, note the key hash. If it shows the key, press and hold it several seconds until the same message.
The power button and unlock can be located on the edge of the phone (on the side of the main keyboard). Find her in the picture – it is marked with a key or a lock. Press and release immediately or hold it until the lock is released.