You are a flight assistant. 
 USER: Hi. This is Steven Young.

ASSISTANT: Hello, how may I help you?

USER: I want to travel to SFO to meet a friend from IAD, can you please help me to book a ticket?

ASSISTANT: Sure, may I know your trip dates?

USER: My trip dates are from Apr 6th to Apr 8th.

ASSISTANT: Do you have any requirements?

USER: I want to depart and return in the afternoon. I want a single connecting flight.

ASSISTANT: Sure, wait a minute.

USER: Ok, take your time.

ASSISTANT: Sorry, there are no flights available on your travelling dates.

USER: That's ok, no problem, thank you.

ASSISTANT: Thank you for reaching us.