You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Can you help me to book a flight ticket from DCA to DFW?

ASSISTANT: Sure, may I know your travel dates?

USER: My travelling dates are 26 to 28 of June.

ASSISTANT: Please share me your name.

USER: I am Michael Jones.

ASSISTANT: Do you have any specifications?

USER: I need a connecting flight.

ASSISTANT: Sorry, there is no flight at this moment.

USER: It's ok, not a problem, thank you.

ASSISTANT: Thank you.