You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello,.

USER: I am Michael Davis.

ASSISTANT: How may I serve you?

USER: I would like to go to Denver to attend my project meeting. Can you help me in booking a flight ticket.

ASSISTANT: Sure, please provide me your journey dates and codes as well.

USER: OK. My journey starts from CA-SFO on 07/05 and should end on 07/07. And my destination is CO-DEN.

ASSISTANT: OK, wait for a minute. I will revert you with availability.

USER: OK.

ASSISTANT: Sorry to inform you that there is no available with your specifications.

USER: OK, Thank you for your service.

ASSISTANT: Thank you. Have a good day.