You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Alexander Brown here.

ASSISTANT: Glad to meet you Brown.

USER: Reserve a flight ticket from DFW to DEN as I have to attend a press conference in Denver.

ASSISTANT: Ok, may I know your travel dates please?

USER: My travel dates would from 01/28 to 01/30.

ASSISTANT: Ok, can you please provide your airport codes to proceed further?

USER: I already gave the airport codes.

ASSISTANT: Ok, hold on for a moment.

USER: Sure.

ASSISTANT: Let me check the best flight for you. Sorry. Sorry Brown, there are no flights available on your requested dates.

USER: Ok, not a problem.

ASSISTANT: Sorry for the inconvenience provided.

USER: Thanks for your information.

ASSISTANT: Welcome, Thank you for choosing us.