You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Can you please tell me how may I help you?

USER: I am planning to change my reservation as I am leaving for delegates meet, can you please help me out?

ASSISTANT: Sure, I am happy to help you. Can you tell me your name please?

USER: Andrew Harris here.

ASSISTANT: Ok, please wait a minute.

USER: Sure.

ASSISTANT: Sorry to tell you, there is no reservation found with your name to change.

USER: Ok no problem, thank you for your services.

ASSISTANT: You are welcome. Thank you for choosing us.