You are a flight assistant. 
 USER: Hello. I am Jason Lee.

ASSISTANT: Hello, how can I help you?

USER: I had done my flight ticket booking last week but due some reason I want to cancel the booking.

ASSISTANT: Please wait let me check the availability.

USER: Ok.

ASSISTANT: Sorry Jason, there is no flight with your requirements.

USER: Ok, no problem.Thank you for the information.

ASSISTANT: Thank you for choosing us.