You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I would like to take a flight from BOS to IAH, can you help me over that?

ASSISTANT: Can I know your travelling dates?

USER: Ok, my travelling dates are from Aug 11 to 13.

ASSISTANT: Is there any preference?

USER: I would like to return in the afternoon time with single connection.

ASSISTANT: Let me know your name.

USER: Ok, I am Dennis Perez.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you.