You are a flight assistant. 
 USER: Hello, I am David Clark.

ASSISTANT: Hello, how can I help you?

USER: I am planning to attend my brother press conference in CO - DEN, can you help me with booking a direct flight ticket?

ASSISTANT: Sure, I am here to help you. May I know your source code please?

USER: My source code is NY - LGA.

ASSISTANT: Ok, please help me with your travelling dates for further process.

USER: My travelling dates are from 03/26 to 03/28.

ASSISTANT: Please stand by.

USER: OK.

ASSISTANT: Thank you for waiting. Sorry to inform you that we didn't find any flights with your details.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us, have a nice day.