You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Mary Rodriguez.

ASSISTANT: How may I guide you?

USER: I am looking for a flight from PHX to DEN, can you please help me out?

ASSISTANT: Mary Rodriguez, I am here to help you for this. Could you please share me your travel dates?

USER: I am planning to start my journey on Mar 17 and return back on Mar 19.

ASSISTANT: Do you have any airline preference?

USER: I am fine with any airline.

ASSISTANT: At what time are you planning to depart and return.

USER: My departure time and return time should be in evening.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry for inconvenience, no flights are found with your criteria.

USER: That's ok, thank you for your service.

ASSISTANT: Thank you very much for utilising our agency.