You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Raymond Thompson.

ASSISTANT: How may I best serve you today?

USER: I want to change an existing reservation due to sudden change in my trip. Can you help me?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please wait a moment, I will check the reservation list and get back to you.

USER: Ok.

ASSISTANT: Raymond Thompson, we could not found any active reservation on your name.

USER: No issue. Thank you.

ASSISTANT: Thank you so much for choosing us.