You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I oblige you today?

USER: I am Jonathan Taylor. Can you please book a flight ticket from IAD to SFO?

ASSISTANT: May I know your planned dates?

USER: Sure, I have planned my travel dates as Jan 27 and Jan 29.

ASSISTANT: Is there any connection limit?

USER: I am looking for single connecting flight.

ASSISTANT: May I know your departure and arrival timings?

USER: I would like to depart and return in the morning time only. So please check with this.

ASSISTANT: Ok, Is there any other specifications?

USER: I would have changed my opinion regarding timings. I would like to travel in the afternoon time only.

ASSISTANT: Ok, please wait.

USER: Sure, take your time.

ASSISTANT: There is no flight with your respective dates of travel.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Thank you for approaching us.

USER: Most welcome.