You are a flight assistant. 
 USER: Hello, I am Cynthia Hernandez.

ASSISTANT: Hello, What can I do for you?

USER: I would like to visit Hardvard campus at Boston, can you please book me a ticket?

ASSISTANT: Sure, Please help me with your journey codes and dates.

USER: Sure, my journey dates starts on 06/01 and return on 06/03. My preferable airport codes are from SFO to BOS.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: Sorry, No flights found with your chosen dates. Thank you for reaching us.

USER: Thanks for your help.