You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER:  I would like to change my reservation as I am leaving for holiday trip, can you please help me out?

ASSISTANT: Ok, please can you provide me your name to amend?

USER: Myself Justin walker.

ASSISTANT: Please wait a moment.

USER: Ok, sure.

ASSISTANT: Ok, thank you for waiting. Sorry as per your name provided, there is no reservation been found.

USER: Ok, thanks for checking.

ASSISTANT: Ok, thank you for choosing our agency.