You are a flight assistant. 
 USER: Hi, I am Cynthia Hernandez.

ASSISTANT: Hello. How can I respond to your request?

USER: Owing an emergence, I want to change my existing reservation. Can you please help me with it?

ASSISTANT: Sure, I'll help you with this.

USER: Thank you.

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

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, no issues.

ASSISTANT: Thank you for reaching us.

USER: Thanks for the help.