Unlock sample schema in Oracle DB

SQL> CONN HR/HR@DBWARE
ERROR:
ORA-28000: the account is locked


Warning: You are no longer connected to ORACLE.
SQL> CONN SCOTT/TIGER@DBWARE
ERROR:
ORA-28000: the account is locked


SQL> CONN /@DBWARE AS SYSDBA
Connected.
SQL> ALTER USER HR IDENTIFIED BY HR ACCOUNT UNLOCK;

User altered.

SQL> ALTER USER SCOTT IDENTIFIED BY TIGER ACCOUNT UNLOCK;

User altered.