Not a able to kill the DB session in Postgres RDS

We are trying to killing one of DB session but not able to do it. Tried with following command getting "TRUE" after issuing command. Still we can see the session is active.

select pg_terminate_backend(933);

pg_terminate_backend
t (1 row)

session:

933 | -1 days -01:51:38.165893 | test | SELECT col1,col2,col3 FROM test_table "PC0" WHERE ( col1 LIKE $1 ) ORDER BY 3 ASC;

can anyone please help me to resolve this.
We are using Postgres-9.3 RDS

I found the answer to this on stack overflow, basically you don't have rdsadmin privileges so you can only terminate sessions for your own username. https://stackoverflow.com/questions/22713375/permissions-for-pg-terminate-backend-on-amazon-rds

StackExchange Database Administrators Q#207570, answer score: 3