You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I guide you?

USER: Barbara Hill here. Can you book me a ticket from ATL to LGA?

ASSISTANT: Sure, can I know your preferable dates?.

USER: I would like to travel on 07/22 and 07/24.

ASSISTANT: I am sorry, there are no flights available. Thankk you.

USER: No issues, thank you for the help.