You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Myself Andrew Johnson from Las Vegas. I want to change my travel dates in my previous reservation. Can you please help me with that?

ASSISTANT: Please wait a moment.

USER: Ok, thank you for your response.

ASSISTANT: Sorry, no reservation found by your name.

USER: Oh! It's ok no problem.

ASSISTANT: Thank you.

USER: Thank you for your information.