You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Emily Smith.

ASSISTANT: How may I be of your service?

USER: Due to sudden work, I need to change my reservation. Can you please help me with it?

ASSISTANT: Sure, I'll help you in changing an existing reservation.

USER: Thank you.

ASSISTANT: Please wait a moment I will check the reservation status.

USER: Ok.

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: Ok, not an issue. Thank you.

ASSISTANT: Thank you for opting us.