You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: Michael Smith here. I want to change my reservation because of my office work, can you help me?

ASSISTANT: Sure, I am happy to help you.

USER: Ok, please check with my previous booking and let me know the status. I will be waiting for your response.

ASSISTANT: Please give me a moment to check out your previous reservation status.

USER: Ok, take your time.

ASSISTANT: Sorry to inform you that, we couldn't find any reservation under your name in our records.

USER: Oh! That's fine, thank you for checking.

ASSISTANT: Thank you for approaching us.

USER: Most welcome.