You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: My name is Benjamin Walker, can you help me to book a flight ticket from ATL to DEN?

ASSISTANT: Sure, I will help you to book a flight ticket. Can you please share me your travelling dates?

USER: Ok, please book for the dates Aug 16 and Aug 18 respectively.

ASSISTANT: Please give me a moment.

USER: Ok, take your time.

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

USER: That is ok, thank you for assisting me.

ASSISTANT: Welcome, have a nice day. Thank you for choosing us.