It should be one of these:
bounce_queue_lifetime = 1d maximal_queue_lifetime = 1d
Hi, Thanks for your quick answer.
I think it is
maximal_queue_lifetime = 1d
I got it from below URLs.
http://www.postfix.org/rate.html *maximal_queue_lifetime* (default: 5 days) How long a message stays in the queue before it is sent back as undeliverable. Specify 0 for mail that should be returned immediately after the first unsuccessful delivery attempt
http://archives.neohapsis.com/archives/postfix/2000-10/1271.html