You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

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

ASSISTANT: Sure, I am oblige to help you.

USER: Thanks.

ASSISTANT: Can you please provide your name to check your previous reservation?

USER: Sure, my name is Virginia Walker.

ASSISTANT: Ok, please wait a moment to check.

USER: Ok.

ASSISTANT: Sorry to inform you that, there is no reservation exists with the name of Virginia Walker.

USER: Oh! It's ok not a problem, thank you for your information.

ASSISTANT: Thank you for reaching us, have a great day.