No rows data in v$active_session_history

Hi,

There no rows data in v$active_session_history of our Oracle EBS database. It does not happen before.

SQL> select count(*) from v$active_session_history ;

  COUNT(*)
----------
         0

The control_management_pack_access parameter value :

SQL> show parameter control_management_pack_access

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
control_management_pack_access       string      DIAGNOSTIC+TUNING


The database version:

SQL> select * from v$version ;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE    11.2.0.2.0      Production
TNS for Solaris: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production


Search the error in alert log database, but I could not assure which error that perhaps has relation with this issue.