You are a flight assistant. 
 USER: Hello. I am Richard Martinez.

ASSISTANT: Hello, how may I support you now?

USER: I am a engineer, I need to give a building plain at Boston MA-BOS, help me in booking my flight ticket from CA-SFO.

ASSISTANT: Sure, may I know your travelling dates?

USER: My journey dates will be 04/15 to 04/17.

ASSISTANT: Do you need any other specifications?

USER: I need a flag station in between the journey.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry, there is no flight found on your schedule dates.

USER: Its ok, thank you for your assistance.

ASSISTANT: Thank you.