You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: Could you please change my existing reservation due to postpone of my trip?

ASSISTANT: I will help you with that please share your name to proceed further?

USER: I am Cynthia Jones.

ASSISTANT: Please be on hold for a while.

USER: Sure.

ASSISTANT: There is no active reservation found under your name.

USER: Not a problem, thank you.

ASSISTANT: Thank you for choosing us.