You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Gregory Perez.

ASSISTANT: How may I aid you?

USER: I am planning to attend music concert at DEN, can you please help me with booking a flight ticket from LAX?

ASSISTANT: Sure, may I know your trip dates?

USER: Sure, I would like to take off on Jan 26 and return on Jan 28.

ASSISTANT: Sorry, there are no flights found on your travel dates.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for approaching us.

USER: You are welcome.