DBSNMP password

 

SQL>select username, account_status, expiry_date from dba_users order by account_status

VERSANT_YAMINI OPEN 05-12-12

VERSANT_SAI OPEN 05-12-12

DBSNMP LOCKED(TIMED) 27-03-14

Note: I changed the password using

alter user dbsnmp identified by <new_password> account unlock;

But after sometime when I query 

"select username, account_status, expiry_date from dba_users order by account_status".. The results are coming

DBSNMP LOCKED(TIMED) 27-03-14

Pls help me to get rid of it.  

Regards,