You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I am Katherine Rodriguez. As my long trip with my friends has been cancelled, so I want to change my resent reservation.

ASSISTANT: Ok, I will help you. Please wait for a while.

USER: Sure.

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

USER: No problem. Thank you for your assistance.

ASSISTANT: Thank you for opting us, have a good day.