You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Brenda Brown here.

ASSISTANT: What can I do for you at this time?

USER: I need your help in booking of a flight between SFO and IAD, can you please help me out with booking of a flight ticket on those locations?

ASSISTANT: Yes, I can help you.

USER: Thank you.

ASSISTANT: Will you please provide your trip dates?

USER: I want to take off from my location on 02/10 and please book a return ticket on 02/12.

ASSISTANT: Please hold on for a moment.

USER: Sure, take your time.

ASSISTANT: I could not found any flight on the dates which you have provides.

USER: Oh! So sad to hear. Anyway, I will choose another alternative to go there.

ASSISTANT: Sorry for the trouble caused to you. Have a nice day.

USER: Thank you for the information.