You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: I want to book a flight ticket from Dallas to attend a client meeting in Washington , can you help me to book a flight ticket with single connection?

ASSISTANT: Sure, may I know your trip dates?

USER: 10/17 and 10/19 are my planned trip dates.

ASSISTANT: Do you require any stopovers in your journey?

USER: I already mentioned above.

ASSISTANT: Do you have any other requirements?

USER: I want to depart in the evening.

ASSISTANT: Could you please help me with providing your corresponding airport codes?

USER: My boarding and landing airport codes are DFW and DCA.

ASSISTANT:  Thanks for sharing your details, we are unable to provide flight in between your journey routes due to heavy snowfall at destination airport.

USER: No issues, I'll choose any alternative. Thank you.

ASSISTANT: Please share your name?

USER: I am Betty Baker.

ASSISTANT: Thank you.