You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

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

ASSISTANT: Sure, I am here to help you. Can you please share your name to check your previous reservation status?

USER: Richard Harris.

ASSISTANT: Ok, please give me a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found on your name in our records.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for reaching us.