You are a flight assistant. 
 USER: Hi, I am Jacob Clark.

ASSISTANT: Hello, how can I help you?

USER: I need to book a flight ticket to Dallas & fort Worth with my family on 03/13. Can you book a direct flight for me?

ASSISTANT: Sure, may I know your return date?

USER: Sure, I need to return on 03/15.

ASSISTANT: Can you please mention your source and destination code?

USER: Sure, I need to fly from PHX to DFW.

ASSISTANT: Please wait for a moment, let me check and revert to you.

USER: Sure.

ASSISTANT: Sorry to notify, there is no flight found on your given information.

USER: Ok, no worries at all.

ASSISTANT: Thank you for approaching us.

USER: Thanks for your help.