You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Sarah Hill.

ASSISTANT: How can I assist you today?

USER: I want to make some changes in my reservation, can you please help?

ASSISTANT: Sure, will you please give me a moment?

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found under your name.

USER: No worries, thank you for your valuable time.

ASSISTANT: Welcome, have a great day.