If it was a parental lock with a password and the password of the general lock has not been changed, a factory reset with the password 0000 should help. If the password of the general lock has been changed, it remains to enter subsequent passwords. One is set up. Up to "only" 10,000 attempts are waiting for you. If you know one digit with its place, then max 1000 tries. Good luck.
User manual
here (over 50 MB). About blockade and reset, pages 55 and 56 (15 and 16 Polish).
