You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you today?

USER: Can you please help me in changing my recent reservation?

ASSISTANT: Sure, we are here to help you. I need some basic information to check your ticket details, can you please tell me your full name?

USER: Myself Mary Collins.

ASSISTANT: Ok, give me some time to check the reservation status.

USER: Sure, I will wait.

ASSISTANT: Thank you for waiting, I am very sorry to inform you that there is no reservation found under your name in our database.

USER: Thank you for your information.

ASSISTANT: Thank you for approaching us.