You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you at this minute?

USER: I am planning to go for holiday trip with my friends to Boston. So, please reserve me a flight ticket under my name Barbara Miller.

ASSISTANT: Sure, I am here to help you with that. Can I know your planned trip dates?

USER: My planned trip dates are Oct 29 and Oct 31.

ASSISTANT: Ok, do you have any other specifications?

USER: My depart time should be afternoon.

ASSISTANT: Ok, may I know your airport codes?

USER: I wish to board from DEN to reach BOS.

ASSISTANT: May I know your class preference?

USER: I am comfortable with any class.

ASSISTANT: Sorry to say that, there are no flight's available based on your travelling dates.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your response.