You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am John Green.

ASSISTANT: What kind of service that you are looking for?

USER: I had done my previous reservation with wrong dates, can you cancel my reservation?

ASSISTANT: Yes, is the ticket booked with your name only?

USER: Yes, please check with my name.

ASSISTANT: Sorry, I could not find any ticket booked on your name.

USER: It's ok. Anyway, thank you for your immediate response.

ASSISTANT: Thank you, have a nice day.