You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you?

USER: Can you please help me to reserve a flight ticket from Phoenix? Because I have to attend a meeting in Denver.

ASSISTANT: Sure, May I know the travelling dates?

USER: Thank you. I am willing to travel on the dates of Oct 19 and Oct 21.

ASSISTANT: Please help me with your journey codes.

USER: The preferable journey airport codes are PHX and DEN.

ASSISTANT: Do you have any connection limit?

USER: Yes, I am looking for a direct flight.

ASSISTANT: Is there any other requirements?

USER: I need a flight which is returning in the morning time which is an economy class flight.

ASSISTANT: May I know your name?

USER: My name is Anthony Allen.

ASSISTANT: Please wait a moment.

USER: Ok, take your time. I will wait for your response.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: It's ok, not a problem with that. I will choose some other source to travel. Anyhow thank you for checking the flight availability.

ASSISTANT: Thank you for choosing us.