You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Patricia Clark.

ASSISTANT: How may I assist you?

USER: Can you help me in changing my previous reservation?

ASSISTANT: Sure, I will help you. Please wait a minute.

USER: Sure.

ASSISTANT: There is no reservation found under your name in our records.

USER: It's fine. Anyway, thank you for your help.

ASSISTANT: Most welcome.