You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Debra Turner here.

ASSISTANT: Debra Turner, how may I assist you today?

USER: I want to change my ticketed flight, such as the dates and destination. So can you help me in change of flight ticket reservation?

ASSISTANT: Sure, I will try to help. Please allow me a minute.

USER: Ok.

ASSISTANT: Thank you. Debra Turner, I am really sorry to inform you that there is no flight ticket booked on your name.

USER: Ok, that is not a problem. Thanks for your information.

ASSISTANT: Thank you for reaching us. Have a great time.