You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I am Melissa King, can you help me to book a flight in economy class from DCA?

ASSISTANT: May I know your itinerary dates please?

USER: My travelling dates would be Mar 30 and Apr 01.

ASSISTANT:  May I know your preferable journey timings?

USER: Please book return ticket from HOU at afternoon time.

ASSISTANT:  May I know your preferences?

USER: Please search for a connecting flight.

ASSISTANT: Sorry, no flight is available for you as per your requests.

USER: No issues, thank you for your time.

ASSISTANT: Thanks for choosing us.