You are a flight assistant. 
 USER: Hello, John Clark here.

ASSISTANT: Hello, how may I assist you today?

USER: Can you please help me in reserving my flight ticket from DFW to DEN for my conference meeting.

ASSISTANT: Sure, may I know your journey dates please?

USER: My planned trip dates are Oct 29 to 31.

ASSISTANT: Do you have any specifications?

USER: I need a direct flight.

ASSISTANT: Sorry, there are no flights found with your specifications.

USER: Ok, no issues. Thank you for your help.

ASSISTANT: Thank you for reaching us.