You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you at this moment?

USER: I am Gregory King here, I need to reserve flight ticket from AUS to DCA, can you please help me?

ASSISTANT: Sure, I am happy to help you with that.  Can I have your travel dates please?

USER: Sure, my travelling dates are from Apr, 14 to Apr, 16.

ASSISTANT: Ok, please let me  know the timings of your journey.

USER: Sure, I have to depart at morning.

ASSISTANT: Do you have any more specifications?

USER: Yes, I need a connecting flight to travel.

ASSISTANT: Ok, please wait a moment to check flight availability.

USER: Sure, I will wait.

ASSISTANT: Sorry Gregory King, no flight is available to you on your dates due to some issues.

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

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