You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am George Roberts.

ASSISTANT: Can you please tell me how may I help you?

USER: I would like to book a ticket from BOS to IAD, can you please help me out?

ASSISTANT: Sure, I am here to help you with the ticket booking. Can you please tell me your travel dates?

USER: I am travelling on these dates May 27th and 29th.

ASSISTANT: Ok, do you have any preferences?

USER: I need return time in the evening.

ASSISTANT: Sorry to inform you that, I have not found any flight which is returning in the evening time on these dates.

USER: Ok no problem, thank you for your services.

ASSISTANT: You are welcome. Thank you for consulting us.