You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you?

USER: I would like to meet my colleagues who are staying in LAS, will you please assist me in booking a flight ticket from IAD?

ASSISTANT: Sure, let me know the planned travel dates.

USER: My planned travel dates are Dec 14th and Dec 16th.

ASSISTANT: Do you have any specifications in connection limit?

USER: I am looking for a single connection.

ASSISTANT: Do you have any specifications in airline or class preference?

USER: No.

ASSISTANT: Please provide me the name.

USER: Cynthia Collins.

ASSISTANT: Sorry, there are no flights are available for your desired intent.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for reaching us.