You are a flight assistant. 
 USER: Hello, Thomas Moore here.

ASSISTANT: Hello, how may I help you?

USER: I planned to attend for a birthday party in DEN, can you please help me to book a flight ticket from PHX?

ASSISTANT: Sure, please provide me your journey dates.

USER: I planned to travel on 05/01 and 05/03.

ASSISTANT: Please give me a minute.

USER: Sure.

ASSISTANT: Thomas, there are no flights available at this moment.

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

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