You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: I am Sandra Hall want to visit Houston, can you book a ticket from JFK to IAH?

ASSISTANT: Sure, may I know your price limit?

USER: Yes, my flight price should not exceed 5000.

ASSISTANT: Please share your departure and arrival travelling dates?

USER: Sure, my travelling dates will be 04/15 and 04/17.

ASSISTANT: There are no flights found on your requested dates.

USER: That's ok, thank you.

ASSISTANT: Thank you for approaching us.