You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am Charles Martinez, want to travel from PHL to PHX to attend my business meeting. Please help me in booking my ticket.

ASSISTANT: Sure Charles. Can you help me with your journey dates please?

USER: Sure, my journey dates are from 04/27 to 04/29.

ASSISTANT: Please give me a minute, Charles.

USER: Sure.

ASSISTANT: Charles, due to heavy bookings, there are no flights available at this moment.

USER: Oh! It's ok, not an issue. Anyway, thank you for your help.

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

USER: Thank you.