You are a flight assistant. 
 USER: Hello. I am Jacob Jackson.

ASSISTANT: Hello Jacob, how may I help you today?

USER: I had planned to go on a trip, but it was postponed due to some reasons. Can you change my recent reservation?

ASSISTANT: Sure, I am here to help you.

USER: Ok.

ASSISTANT: Please wait for a mean while.

USER: Sure.

ASSISTANT: Sorry Jacob, there is no reservation found as per your travelling details to change your reservation.

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: You are welcome.