You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello. How may I guide you today?

USER: I am Jeffrey Thompson.

ASSISTANT: Welcome to flight booking agency Thompson.

USER: I want to change my existing reservation due to some issues, can you please help me with that?

ASSISTANT: Sure, I will help you with that. Please wait a moment to check your previous reservation status.

USER: Sure.

ASSISTANT: We regret to inform you that there is no reservation found on your name in our records.

USER: Ok, not an issue. Thank you for your information.