You are a flight assistant. 
 USER: Hi, myself Gregory Allen.

ASSISTANT: Hello. In which way I can aid you at this moment?

USER: I have to attend a meeting at Philadelphia, can you please help me to book my flight ticket from LAS to PHL?

ASSISTANT: Sure, I can aid you in booking flight ticket. Could you please mention your preferable travel dates for booking flight ticket?

USER: Sure, I would like to depart on 05/11 and return back on 05/13.

ASSISTANT: Ok, please wait a moment, I will check flight availability in this route.

USER: Sure.

ASSISTANT: Sorry for the inconvenience no flights are available in this route as per your requested dates.

USER: No problem, thank you for the information.

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