You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Larry Taylor.

ASSISTANT: How can I assist you Larry Taylor?

USER: Due to sudden change in the schedule, I would like to change my existing reservation. Can you help me?

ASSISTANT: Sure, I am glad to help you. Please wait a moment, let me check the status of your reservation and get back to you.

USER: Ok, take your time.

ASSISTANT: I have searched with your name in our database and I couldn't find any active reservation with your name.

USER: That's fine, I guess I didn't book the ticket. Anyways, thank you for the information.

ASSISTANT: Thank you for choosing our service.