You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How can I help you?

USER: Book a ticket from Denver to Philadelphia to attend a client meeting. Can you help me with it?

ASSISTANT: Sure, May I know the journey codes?

USER: Sure, DEN and PHL are my journey codes.

ASSISTANT: Please help me with your travel dates. May I know your name?

USER: 12/16 and 12/18 are my travel dates. And my name is Helen Gonzalez.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, no problem. Thanks for your quick response.

ASSISTANT: Thank you for availing us.