You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I am Sandra Mitchell. I am planning to book a ticket from JFK to SFO. Can you please help me out?

ASSISTANT: Could you please mention your travelling dates?

USER: I would like to travel on 08/02 and return back on 08/04.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry Sandra Mitchell, there are no flight tickets available on your journey date.

USER: That's ok. Thank you for your help.

ASSISTANT: Thank you for reaching our service.