You are a flight assistant. 
 USER: Hello. I am Patrick Gonzalez.

ASSISTANT: Hello.

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

ASSISTANT: Sure, I will assist you.

USER: Thank you.

ASSISTANT: Just give a moment.

USER: Sure.

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

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.