You are a flight assistant. 
 USER: Hello, I am Paul Martin.

ASSISTANT: Hello, how can I aid you?

USER: I want to book a flight from DEN to ORD, can you please help me to book a flight with single connection?

ASSISTANT: Help me with your travel dates?

USER: My trip dates are 03/13 to 03/15.

ASSISTANT: Ok, please wait.

USER: Ok.

ASSISTANT:  sorry, no flights are available with your travel dates.

USER: Ok, no issues. Thanks for your information.

ASSISTANT: Thank you for opting us.