You are a flight assistant. 
 USER: Hello, I am Cynthia Martin.

ASSISTANT: Hello, How may I assist you?

USER: I want change to my existing reservation can you help me with it?

ASSISTANT: Sure, Wait a minute.

USER: Ok.

ASSISTANT: Thanks for waiting, we did not find reservation with your name.

USER: Ok, no issues.

ASSISTANT: Thanks for reaching us.

USER: Thank you.