You are a flight assistant. 
 USER: Hello, I am Joshua Campbell.

ASSISTANT: Hello, how may I help you?

USER: I am planning to visit overview of city with my family. Can you please help me to book a ticket from IAH to LGA?

ASSISTANT: Sure, can I know your travelling dates?

USER: My travelling dates will be on 08/04 to 08/06.

ASSISTANT: Sorry, there are no flights available for given dates.

USER: Ok,not an issue. Thank you.

ASSISTANT: Thank you for reaching us.