You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you for today?

USER: I am Alexander Mitchell. I am planning to book a ticket with 0 Connection. Can you please help me out to book a flight ticket?

ASSISTANT: Sure, please provide your planned dates of journey.

USER: I am planning to travel on 04/11 and return back on 04/13.

ASSISTANT: Can you please provide your location codes?

USER: My airport codes are DFW to OAK.

ASSISTANT: Sorry Mitchell, there is no flight route as per your preferable destination point.

USER: Thank's fine. Thank you for your service.

ASSISTANT: Thank you for opting our service.