You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you today?

USER: Brian Rodriguez here. I would like to book a ticket from DCA to EWR, can you please help me with that?

ASSISTANT: Sure, Can you please share your preferable journey dates?

USER: The travel dates are from 01/05 to 01/07.

ASSISTANT: Please wait for a minute.

USER: Ok.

ASSISTANT: I am sorry to say that there is no flight found under your details.

USER: That's ok, thank you for your help.

ASSISTANT: Thank you for reaching us.