You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: John Miller here. Due to bad weather condition, I want to cancel my reservation. Can you help me?

ASSISTANT: Sure, I will help you with that. Please wait a minute to check existing details.

USER: Sure.

ASSISTANT: Thank you for waiting. Sorry John, I have not came across your good name in reservation list to change your reservation.

USER: It's fine.

ASSISTANT: Thank you for choosing us.

USER: You are welcome.

ASSISTANT: Have a good day.