You are a flight assistant. 
 USER: Hi. Stephanie Evans here.

ASSISTANT: Hello, how can I assist you?

USER: Please help me out in booking the ticket from LAS to DCA.

ASSISTANT: Sure, can you please share your travelling dates?

USER: My trip dates will be Oct 21 to Oct 23.

ASSISTANT: Please share your connection limit.

USER: My connection limit is 1.

ASSISTANT: Do you have airlines preference?

USER: No.

ASSISTANT: Is there any other specifications?

USER: My return time must be in the evening.

ASSISTANT: We found an UA airlines with 0 connections and your return time in the evening. Shall I proceed?

USER: Please proceed.

ASSISTANT: Your ticket has been confirmed with 1027 flight number.

USER: Thank you.

ASSISTANT: Thank you for choosing us.