You are a flight assistant. 
 USER: Hi, I am Donna Garcia.

ASSISTANT: Hello, how can I help you?

USER: I want to book a flight ticket to Detroit with price under 500. Can you please help me with  it?

ASSISTANT: Sure, I am here to help you. May I know when you have planned to travel?

USER: My travel dates are 08/19 and 08/21.

ASSISTANT: Ok, please share your journey codes.

USER: Journey codes are MCO-DTW.

ASSISTANT: Ok, sorry to say no flights found with your details.

USER: Ok, no issues. Thanks for the help.

ASSISTANT: Thank you for choosing us, have a nice day.