You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I am planning to travel from DFW to DEN, help me in booking a flight?

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

USER: I like to travel on Aug 24 to 26.

ASSISTANT: Do you have any other requirements?

USER: I want direct flight and I will be back on evening.

ASSISTANT: Can I know your name please?

USER: I am Thomas Edwards.

ASSISTANT: Sorry, we regret to inform you that there is no flight available as per your request.

USER: That's ok, thank you.

ASSISTANT: Most welcome.