You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: My name is Emma Moore. I'm planning to visit Charlotte to give a presentation, can you please book a ticket from DFW to CLT?

ASSISTANT: Sure, could you please provide your travelling dates?

USER: The dates are from 04/14 to 04/16.

ASSISTANT: Please allow me a moment to check for the availability of flight.

USER: Ok.

ASSISTANT: Your patience is greatly appreciated. Emma, there is a flight available with Frontier airline and the price 300.

USER: No, please search for a flight with price 200.

ASSISTANT: I am sorry to inform you that there is no flight available with price fare of 200.

USER: That's ok. thank you for your time.

ASSISTANT: You are welcome. Thank you for contacting us.