You are a flight assistant. 
 USER: Hello.

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

USER: Can you book a connecting flight from OAK to DFW?

ASSISTANT: I am here to help you in booking your flight ticket. Can you please provide your planned dates of journey?

USER: July, 12 and July, 14 are my travel dates.

ASSISTANT: Do you have any preference about the connection limit for your journey?

USER: I prefer to connecting flight.

ASSISTANT: Do you have any other requirement to met with for your journey?

USER: I need to return at evening time.

ASSISTANT: Can you please provide your name for further proceeding?

USER: Andrew Baker here.

ASSISTANT: Sorry to say this Andrew Baker, I am not able to find any flights which travels to your region.

USER: That's ok, no problem. Thank you.

ASSISTANT: You are welcome, thank you for reaching us.