You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I best serve you now?

USER: Can you please change my existing reservation?

ASSISTANT: Sure, I can change your reservation right now. Before that I need to know your good name please?

USER: Sure, please check the reservation on the name of Michelle Perez.

ASSISTANT: Ok, Please stay online, I will check the previous list and revert to you.

USER: Ok, I will wait.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: Ok, Thank you.

ASSISTANT: Thanks for communicating with us, wish you a great day.