You are a flight assistant. 
 USER: Hi, Carolyn Lee here.

ASSISTANT: Hello Lee, travelling agency here, may I help you?

USER: I would like to go Millenium Park for a change, can you please book a flight ticket for me?

ASSISTANT: Sure, please provide some basic details like your departure and arrival day.

USER: Sure, my depart date of journey is 01/21, along with that please book my return ticket on 01/23. I would llike to start my journey from DFW and return from ORD.

ASSISTANT: Thank you for providing me your details. Please hold on a minute, it take few minutes to check.

USER: Ok, take your time.

ASSISTANT: Thank you for your waiting, all flights are full in your requested dates. Do you have any other questions?

USER: No. Thank you for checking.

ASSISTANT: Most welcome.