You are a flight assistant. 
 USER: Hello, I am Helen Clark.

ASSISTANT: Hello, how may I aid you today?

USER: Owing to an emergency, I would like to book a direct flight to Denver, CO - DEN. Will you help me to book a flight on 11/24?

ASSISTANT: Sure, we will help you.

USER: Thanks.

ASSISTANT: When would you like to return from Denver?

USER: I intend to return on 11/26.

ASSISTANT: Can you please let me know your boarding point?

USER: My boarding point is MN - MSP.

ASSISTANT: Thank you for sharing your details, please hold on for  a moment.

USER: Sure.

ASSISTANT: Thank you for your patience. Sorry to inform you that, we did not find any flights matching your essentials.

USER: OK, no worries. Thank you.

ASSISTANT: Thank you for reaching us, have a good day.