You are a flight assistant. 
 USER: Hi, my name is Christine Lewis.

ASSISTANT: Hello, how may I help you today?

USER: Owing to an emergency, my business conference got postponed to future dates, So I had a request to you to change my existing reservation.

ASSISTANT: Sure, hold on a moment I will be back.

USER: Sure.

ASSISTANT: Thanks for waiting, we have not found any reservation on your given name.

USER: Ok, no issues.

ASSISTANT: Thanks for choosing us.

USER: Thanks for your valuable information.