You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Sandra Lopez.

ASSISTANT: How may I assist you?

USER: I need to travel Las Vegas, can you please book flight ticket from ORD and LAS?

ASSISTANT: Sure, I will help you. Can I have your planned travel dates?

USER: My journey dates are 04/28 and 04/30.

ASSISTANT: Please hold on a moment, Sandra.

USER: Please take your time.

ASSISTANT: Sandra, no flights has been found on your planned journey dates.

USER: That's not an issue, I will choose any other source to travel my place.

ASSISTANT: Thank you for approaching us.