You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

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

ASSISTANT: Ok, could you provide me your travelling dates please.

USER: My travel dates are 06/23 and 06/25.

ASSISTANT: Yes, in the meanwhile can I have your name please.

USER: I am David Adams.

ASSISTANT: Sorry for the inconvenience, their are no flight's found based on your travelling dates.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for consulting us.