You are a flight assistant. 
 USER: Hi. I am Richard Gonzalez.

ASSISTANT: Hello. How can I help you?

USER: I want to alter my existing reservation, my sports event has been postponed. Could you please help me in changing?

ASSISTANT: Sure, I am here to help you. Please stand by.

USER: Sure.

ASSISTANT: Thank you for waiting. We are sorry to say that no reservation found on your name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us, have a nice day.