BUG #16145: Not able to terminate active session

The following bug has been logged on the website:

Bug reference: 16145
Logged by: MOHAN KUMAR DORAIRAJ
Email address: mohankumar(dot)dorairaj(at)globalfoundries(dot)com
PostgreSQL version: 11.2
Operating system: Red Hat Enterprise Linux Server release 7.6 (Maipo
Description:

Not able to terminate active session even though used below commands

postgres=# SELECT pg_cancel_backend(16647);
pg_cancel_backend
-------------------
t
(1 row)

postgres=# SELECT pg_terminate_backend(16647);
pg_terminate_backend
----------------------
t
(1 row)

postgres=# select pid,application_name FROM pg_stat_activity where
application_name IS NOT NULL AND state = 'active';
pid | application_name
-------+------------------------
16647 | PostgreSQL JDBC Driver
19879 | psql