You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Shirley Nelson.

ASSISTANT: Nelson, how can I assist you?

USER: I would like to celebrate my brother's birthday at Fort worth, please help me in booking my ticket.

ASSISTANT: Sure, I am happy to help you, can you please provide me your travel dates?

USER: My planned dates are from 04/26 to 04/28.

ASSISTANT: Ok, let me know your source and destination airport codes.

USER: My airport codes are from DEN to DFW.

ASSISTANT: There is a flight available in Spirit airlines with 1 connection. Shall I book your ticket?

USER: Please check the flight with 0 connection.

ASSISTANT: Sorry Nelson, there are no direct flights available on your preferred dates.

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

ASSISTANT: Thank you for choosing us and have a nice day.