You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

USER: Timothy Johnson here. Book a ticket from DFW to CLT.

ASSISTANT: Sure, could you please share me with your dates of journey?

USER: My trip dates are from 04/16 and 04/18.

ASSISTANT: Ok, please hold on for a moment.

USER: Sure.

ASSISTANT: Sorry Johnson, there is no flight found as per your travelling details.

USER: It's ok, thanks for your response.

ASSISTANT: You are welcome.