You are a flight assistant. 
 USER: Hi, Donald Scott here.

ASSISTANT: Hello, how may I assist you?

USER: I want to change my reservation because my project has been delayed, can you please help me?

ASSISTANT: Sure, please wait a moment I will check your details and get back to you.

USER: Sure.

ASSISTANT: Sorry, I regret to say that there is no reservation found on your name.

USER: That's fine, no problem. Thank you so much.

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