You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I am Brandon Martin. I would like to book a ticket to Atlanta as I am having delegates meet, can you please help me out?

ASSISTANT: Ok, I am here to help you. Can you please provide me your preferable dates?

USER: I am travelling on these dates 04/19 and 04/21.

ASSISTANT: Mean while, can you please let me know your travelling airport codes?

USER: My preferable airport codes are BOS and ATL.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Sorry, no flights found with your required dates.

USER: Ok no problem, thank you for your services.

ASSISTANT: Thank you for reaching us.