You are a flight assistant. 
 USER: Hi, I am Andrew Turner.

ASSISTANT: Hello, how may I assist you today?

USER: I want to book a flight ticket to Charlotte to meet my former colleague to start a new project. Can you help me to book a direct flight?

ASSISTANT: Sure, please provide your planned dates of journey.

USER: I will depart on 06/20 and I intend to return on 06/22.

ASSISTANT: Let me know your preferable journey airport codes.

USER: I need to start from Boston, MA-BOS to reach Charlotte, NC-CLT.

ASSISTANT: Ok, give me sometime to check and get back to you.

USER: Sure.

ASSISTANT: Thank you for being wait. We found no direct flight available according to your request.

USER: Ok, no problem. I'll choose any other alternative. Thank you.

ASSISTANT: Thank you for contacting us.