You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I assist you?

USER: I would like to go for shopping with my family to Ferry building market place, located at San Francisco, CA - SFO. Can you book a flight ticket for me within the price of 500?

ASSISTANT: Do you need any connection in between your journey?

USER: I prefer only a single connection.

ASSISTANT: When would you like me to book a ticket?

USER: Please book my ticket in the dates of 01/21 and 01/23.

ASSISTANT: Can you please assign your source airport?

USER: My source is from TX - HOU.

ASSISTANT: To proceed further can I know your good name please?

USER: I am Christine Clark.

ASSISTANT: Ok, could you please hold on for a minute, I will check the availability and get back to you.

USER: Thank you for helping me.

ASSISTANT: We are very sorry to notify you that there is no flight found based on your details. Thank you for choosing us, Have a great day.

USER: Thank you.