You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: Can you please make a reservation from LGA to DCA?

ASSISTANT: Sure, could I have your journey dates, please?

USER: My journey dates are on Mar 28th and 30th.

ASSISTANT: Do you have any specifications?

USER: I need a flight with single connection. My return flight time should be in the evening.

ASSISTANT: May I know your good name?

USER: My name is Sarah Miller.

ASSISTANT: Sorry, there are no flights available as per your requirements.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.