You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am Richard Martinez. I want to attend my friend marriage at SFO, can you please book me a ticket from DEN?

ASSISTANT: Sure, may I know your travel dates.

USER: I have planned to travel on 06/22 and 06/24.

ASSISTANT: How much can you afford for this journey?

USER: I can afford up to 500.

ASSISTANT: Ok, please wait a moment.

USER: Ok, I will wait.

ASSISTANT: Sorry to inform, no flights found with your requirement.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thanks for reaching us.