You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: I am Nancy Jackson. Due to an emergency I want to change my existing reservation. Can you please help me with it?

ASSISTANT: Sure, please wait for a moment I will get you back.

USER: Sure.

ASSISTANT: Thanks for waiting, we have not found any reservation with your given name.

USER: Not a problem, thank you.

ASSISTANT: Thank you for reaching us.