You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I be at your service today?

USER: Daniel Lewis here. I want to expand my casino business from Las Vegas to San Francisco. Could you help me to book my flight ticket?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My itinerary dates are June 24 and June 26.

ASSISTANT: Please share me your source and destination codes.

USER: My genesis and terminus airport codes are LAS and SFO.

ASSISTANT: Do you have any other specifications?

USER: I want to depart in the morning and return in the evening.

ASSISTANT: Sorry for this inconvenience, I could not find any flight with your requirements.

USER: No problem, thank you.

ASSISTANT: Thank you for reaching us.