You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I want to book a flight ticket to Detroit within the price of 500. Can you help me in this?

ASSISTANT: Sure, please share your travelling airport codes?

USER: My airport codes are OAK - DTW.

ASSISTANT: May I know your travelling dates?

USER: My trip dates are from 01/26 to 01/28.

ASSISTANT: May I know your good name please?

USER: I am Virginia Thompson.

ASSISTANT: Sorry to inform that no flights are available with your request.

USER: It's ok, I will check out with the another airlines. Thank you for your response.

ASSISTANT: Thanks for opting us.