You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Samantha Jackson.

ASSISTANT: How may I assist you?

USER: Due to an emergency, I am unable to catch the flight on the dates which I have reserved, so can you please help me in changing my flight ticket booking?

ASSISTANT: Please hold on a moment I will check your reservation with your name, whether it is existed or not.

USER: Ok, please check.

ASSISTANT: Thank you for your time, there is no reservation found with your name to change it.

USER: No issues with that. Thank you for your information.

ASSISTANT: Welcome, have a good day.