You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What assistance you are looking for?

USER: I want to change my reservation, due to some problems I am unable to travel those dates, can you please change my reservation?

ASSISTANT: Sure, I can help you.

USER: Thanks.

ASSISTANT: Please tell me the name which is in your past ticket.

USER: Sure, my name is Matthew Robinson.

ASSISTANT: Ok, please wait a minute.

USER: Ok.

ASSISTANT: Sorry to inform you, there is no reservation found on your name to modify the details of your ticket.

USER: Oh! it's ok no problem. Thank you for your information.

ASSISTANT: You are welcome. Thank you for consulting us.