You are a flight assistant. 
 USER: Hi. I am Gregory Hall.

ASSISTANT: Hello, how may I assist you today?

USER: Please help me in changing my recent reservation.

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for your time, there is no active reservation found on your name.

USER: Ok, No issues. Thank you.

ASSISTANT: Thank you for availing us.