You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Donna Jones here.

ASSISTANT: Donna Jones, how may I render you?

USER: Please help me out in booking the tickets from CLT to HOU.

ASSISTANT: Please share your itinerary dates.

USER: My depart and return trip dates will be Mar 19 to Mar 21.

ASSISTANT: Do you have any specifications?

USER: Yes, I need a break and depart time must be in the afternoon.

ASSISTANT: Do you have any other preferences?

USER: No.

ASSISTANT: Sorry, no flights are available on your route.

USER: That's ok. Thank you.

ASSISTANT: Thank you for reaching us.