You are a flight assistant. 
 USER: Hello. Larry Walker here.

ASSISTANT: Hello, how may I help you today?

USER: I am looking for a economy class flight, can you please reserve a flight ticket from PHX to LAX?

ASSISTANT: Sure, can I know your trip dates?

USER: I am willing to travel on Apr 29 and please book my return ticket on May 01.

ASSISTANT: Do you have any other specifications?

USER: I would like to departure in afternoon time.

ASSISTANT: Do you have any class preference?

USER: I prefer economy class for my trip.

ASSISTANT: Sorry, we could not find any flights available.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for reaching us.