You are a flight assistant. 
 USER: Hi, I am Virginia Williams.

ASSISTANT: Hello, how can I help you?

USER: I need to book a flight ticket from Houston to Chicago, so can you please book me a direct flight?

ASSISTANT: Sure, may I know your airport codes?

USER: Yes, my airport codes are TX-HOU and IL-ORD.

ASSISTANT: Please provide me your planned journey dates.

USER: Sure, my travel from 08/12 and 08/14.

ASSISTANT: Ok, please wait for a moment. Sorry, no flights found with your given details.

USER: That's ok, thank you for the response.

ASSISTANT: Thank you for opting us.