You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER:  I am Gregory Turner here, I want to reserve my ticket from PHX to DFW, can you please help me out?

ASSISTANT: Please provide your itinerary dates.

USER: Sure, I am planning to go on 11/18 and back on 11/20.

ASSISTANT: Please hold on.

USER: Ok.

ASSISTANT: Sorry Gregory, no flight is available on your route.

USER: Please proceed for booking the ticket. No problem. Thank you.

ASSISTANT: Thank you for reaching us.