You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,.

USER: I am Frank Hall.

ASSISTANT: How can I help you today?

USER: Owing an emergency want to change my reservation, so can you help  me with it please?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Please wait a while.

USER: Ok, take your time.

ASSISTANT: Thank you for waiting. I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: That's ok. Thank you for the response.

ASSISTANT: Thank you for approaching us.