You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Mark Martinez here.

ASSISTANT: How can I assist you at this moment?

USER:  I want to sell my house in Dallas, so I want to meet the buyer. Please book my ticket from DEN to DFW.

ASSISTANT: Sure, can you please provide your travelling dates to proceed further?

USER: I want to fly on 10/30 to 11/01.

ASSISTANT: Mark Martinez, there are no flights available on this route with your provided dates.

USER: No problem, thank you for your services.

ASSISTANT: Thank you for contacting us.