You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: Can you help me to change the reservation which I had done last month?

ASSISTANT: May I know your name please?

USER: Ok, please check for the name Patrick Smith.

ASSISTANT: No reservation found in our database.

USER: Ok, that is not a problem. Thank you for assisting me.

ASSISTANT: Thank you.