You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Could you help me to change my existing reservation?

ASSISTANT: Sure, could you please provide me your name?

USER: Sure, my name is Patricia Moore.

ASSISTANT: Sorry, no reservation found for this search.

USER: OK, not an issue.

ASSISTANT: Thank you.

USER: Anyway, thank you for your help.