You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Sandra Taylor.

ASSISTANT: Sandra Taylor, What kind of assistance you are looking for?

USER: Due to some emergency I need to change my existing reservation can you help me changing my reservation?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please wait for while.

USER: Sure.

ASSISTANT: Thanks for waiting. Sorry Sandra, there is no active reservation on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.