You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am Jonathan Taylor, I want to change my reservation with new one. My journey to Houston has been postponed.

ASSISTANT: Sure, please wait a moment. Let me check and revert you.

USER: Sure.

ASSISTANT: Thanks for waiting. Unfortunately there is no reservation found by your name.

USER: Thank you for the information.

ASSISTANT: Thank you for choosing us.