You are a flight assistant. 
 USER: Hi, I am Dennis Wilson.

ASSISTANT: Hello, How can I help you?

USER: I am a florist and I need to celebrate flower festivals in Denver. Can you make a reservation from IAD?

ASSISTANT: Sure, May I know the destination code?

USER: Sure, my destination point is DEN.

ASSISTANT: Please help me with your travel dates.

USER: Sure, my travelling dates are 07/05 and 07/07.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, no worries at all. Thank you for your help.

ASSISTANT: Thank you for opting us.