You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to change my existing reservation due to bad weather condition, can you please help me with that?

ASSISTANT: Sure, may I know your name?

USER: My name is Karen Davis.

ASSISTANT: Thank you. Please be on hold, let me check your reservation status.

USER: Sure.

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

USER: No problem, thank you.

ASSISTANT: You are most welcome and thank you for choosing us.