You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What help is required from our agency?

USER: I want to change my reservation,  due to some health problem I am unable to travel on those dates. So, can you help me?

ASSISTANT: I will help you with that, can you please let me know your name to check the reservation status?

USER: Myself Katherine Edwards.

ASSISTANT: Ok, wait a moment please.

USER: Sure, take your time.

ASSISTANT: Sorry Edwards, there is no reservation found on your name in our database.

USER: That's fine. I will be concerned with another agency.

ASSISTANT: Thank you for choosing our agency.

USER: Thank you for your checking.