You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,. How can I aid you today?

USER: I am Richard Martinez.

ASSISTANT: Thanks for sharing your name.

USER: Please change my existing reservation because, I postponed my meeting.

ASSISTANT: Sure, we are here to help you, please wait.

USER: Ok.

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

USER: Ok, Thank you.

ASSISTANT: Thank you for reaching us.