You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you help me to book a direct flight?

ASSISTANT: Sure, please share your travelling airport codes.

USER: My airport codes are LGA to ORD.

ASSISTANT: On which dates you want me to book your tickets?

USER: My travel dates are July 19 and July 21.

ASSISTANT: Ok, please mention your name.

USER: I am Dorothy Edwards.

ASSISTANT: Do you have any specification?

USER: No, thanks for asking.

ASSISTANT: Sorry, no flights are available on your preferable travel dates.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us, have a nice day.