How to alter a profile in Oracle?

Please login to database server with ssh as oracle user and run that commands.

sqlplus / as sysdba

SQL> ALTER PROFILE engineer LIMIT 
SESSIONS_PER_USER 5
IDLE_TIME 60
CONNECT_TIME 1200;

SQL> exit

-- SESSIONS_PER_USER; Specify the number of concurrent sessions to which you want to limit the user.
-- IDLE_TIME; Specify the permitted periods of continuous inactive time during a session, expressed in minutes. Long-running queries and other operations are not subject to this limit.
-- CONNECT_TIME; Specify the total elapsed time limit for a session, expressed in minutes.