You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Stephen Lewis.

ASSISTANT: What type of assistance that you are looking from our agency Lewis?

USER: In the last month I have reserved a flight ticket on my name to travel to San Francisco to celebrate my father birthday but suddenly there is a meeting on the same date and our college management has informed suddenly to us. So I am unable to travel the trip which I was planned. Can you please help me in changing my flight ticket?

ASSISTANT: Sure, I will do that for you.

USER: Thank you for your positive response.

ASSISTANT: Please wait for a while to check your previous reservation status.

USER: Sure, I will wait for your response.

ASSISTANT: Thank you for waiting, I have checked twice on your name but I got the information that there is no reservation available.

USER: Not an issue with that one, I think it is not booked properly when I have reserved the flight ticket. Thank you for your search and providing your information.

ASSISTANT: Sometimes it might happened like that. Anyway, thank you for reaching us, hope you have a great day.

USER: Welcome.