You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Nicole Robinson.

ASSISTANT: Nicole Robinson, how may I assist you with today?

USER: I am planning to attend a Tennis competition in DCA from DEN. Can you find a flight ticket for me?

ASSISTANT: Good to hear, I will help you by booking a flight ticket for you. Can I know your travelling dates?

USER: Sure, I am planning to travel on these days that is Apr 20 and back on Apr 22.

ASSISTANT: Thank you for the information. Please allow me a minute while I check for available flights.

USER: Sure, take your time.

ASSISTANT: I apologies to inform you that there are no flights as per your preferences.

USER: Ok, not an problem. Thank you for your information.

ASSISTANT: Is there anything else that I can help you with?

USER: Please check with the direct flight.

ASSISTANT: Just to confirm, do you want me to check with the same details provided earlier?

USER: Yes.

ASSISTANT: I have re-verified our database for the flights but I see there are no flights.

USER: Ok, that's fine, no problem.

ASSISTANT: I am sorry for the inconvenience caused.

USER: Thank you for your valuable time.

ASSISTANT: Thank you for reaching us, have a great time.