You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you?

USER: I want to book a ticket from IAD to DFW, can you help me?

ASSISTANT: Sure, may I know your journey dates please?

USER: My journey dates are 04/21 and 04/23.

ASSISTANT: May I know your name please?

USER: Myself Barbara Carter.

ASSISTANT: Barbara, no flights has been found on your dates of journey.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for utilizing our service.