You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to modify my travelling dates, can you please help me to change my reservation?

ASSISTANT: Sure, may I know your name please?

USER: My name is Kenneth Moore.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, there was no reservation found with your given name.

USER: Ok, not an issue. Thank you for informing me.

ASSISTANT: Thank you for opting us.