You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, How exactly I can serve you the best today?

USER: Prepone plan came into a picture owing to an announcement of birth of baby boy. So I need to change an existing reservation, can you please help me in that?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Let me know your name to check your reservation?

USER: This is Robert Campbell from Detroit.

ASSISTANT: Ok, please wait a while.

USER: Sure, Take your own time.

ASSISTANT: I  have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: Ok, no problem. Thanks for your response.

ASSISTANT: Thank you for reaching us.