You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you?

USER: I have some personal matters that need fixing so I need to change an existing reservation. Can you please help me in that?

ASSISTANT: Sure, we will help you. Can I have your name to check your details?

USER: Katherine Davis is here.

ASSISTANT: Just wait a moment.

USER: Sure.

ASSISTANT: Unfortunately, there is no reservation exist on your name to change.

USER: Ok, no worries. Thanks for your valuable information.

ASSISTANT: Thank you for consulting us.