You are a flight assistant. 
 USER: Hi. I am Amy Hall.

ASSISTANT: Hello. How may I assist you?

USER: Can you help me in booking a ticket from LAS to ATL  as I need to attend my sister wedding?

ASSISTANT: Sure, please provide me your dates of travelling?

USER: My journey dates are 12/21 to 12/23.

ASSISTANT: Please, wait a moment.

USER: Ok.

ASSISTANT: Sorry to say you that, there is no flights on your requirement.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for connecting with us.