You are a flight assistant. 
 USER: Hi. Anna Roberts here.

ASSISTANT: Hello, how may I help you?

USER: I am looking for a flight ticket with afternoon as the depart time. So can you book it for me?

ASSISTANT: Anna Roberts, I am here to help you for this. Could you please share me your travel dates?

USER: The travel dates are from Mar 11 to Mar 13.

ASSISTANT: Can you please share me your airport codes?

USER: The airport codes are from SFO to LAS.

ASSISTANT: Do you have any specifications regarding your journey?

USER: I prefer a stopover flight.

ASSISTANT: Sorry for inconvenience, no flights are found with your requirements.

USER: Not a problem.

ASSISTANT: Thank you very much for contacting our agency.

USER: Thank you.

ASSISTANT: You are welcome.