Hello.
Hello, how can I aid you?
I am David Miller. I planning to celebrate my daughter birthday at San Francisco, CA - SFO. Can you please help me with book a direct flight?
Sure, please can I have your planned dates?
I have planned my travelling dates are 04/20 to 04/22.
Please provide me your  origin.
My origin code is Washington DC - IAD.
Sorry, there are no flights with your requirement.
OK, not an issue. Thank you for the information.
Have a good day.