How to handle the undelivered ACL message

[rolanka ()]

Hi Experts,

I have an agent A, in a Container A; it pings an agent B in a Container B, from time to time. When agent B replys with a pong, agent A migrates in Container B. However it seems when agent B becomes online, it receives all the messages, not only one.
So when a message is not delivered because the receiver is not available, how can I detect whether message has been sent or not?

What happen to the message? Does it come back to the sender?
 
Thanks in advance,

Roshan kumara
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