You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Margaret Gonzalez.

ASSISTANT:  How can I aid you?

USER: I need to book a flight ticket from DTW to IAD, Can you please help me for booking?

ASSISTANT: Could you provide me your travelling dates?

USER: 12/12 to 12/14 are my planned trip dates.

ASSISTANT: Do you have any preference?

USER: I need a connecting flight with fare of 1000.

ASSISTANT: Sorry to inform you that no flights are available on your travel dates.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for availing us.