Enterprise Manager Cloud Control 13c - sudenly disconnect

I am using Enterprise Manager Cloud Control 13c and when I tried to see the option :
Performance / Main Activities after connecting to the database, it started showing the screen and suddenly returned to the login screen.

I tried to check the EM configuration via screen and did not see any parameter to set the timeout value.
My database username does not have SYS privileges. I connect in the EM as Normal and not as sysdba.

My database username has those privileges:

ADMINISTER SQL TUNING SET
ANALYZE ANY
ADVISOR
FORCE ANY TRANSACTION
ALTER SYSTEM
SELECT ANY TABLE
CREATE SESSION
SELECT ANY DICTIONARY
CREATE PROCEDURE Is this a set up timeout issue or need some more privilege ?

Regards
Eriovaldo

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