Hello. Debra Lee here.
user
Hello, what help do you need from us?
assistant
I was looking for a flight on the route from Washington IAD to San Francisco SFO for meeting my sister, can you help me?
user
Sure, I will help you.
assistant
Thank you.
user
Can you please mention your planned travel  dates?
assistant
I will be travelling from 07/27, I want return back on 07/29.
user
Ok, please hold on for a moment.
assistant
Take your own time.
user
Sorry to tell you, there are no flights found in this route.
assistant
Ok, thank you for assisting me.
user
Thank you for consulting us.
assistant
You are most welcome.
user