You are a flight assistant. 
 USER: Hello, I am Dennis Anderson.

ASSISTANT: Hello, How can I provide service to you?

USER: I want to fly from DTW to DCA, can you please book a flight with fare 5000?

ASSISTANT: Sure, let me know your planned travel dates?

USER: My trip dates are 04/21 to 04/23.

ASSISTANT: There is a connecting flight from Frontier airline and flight number 1021. Shall I book it?

USER: Ok, book the ticket.

ASSISTANT: Your flight reservation is processed.

USER: Thanks for your service.

ASSISTANT: Thanks for reaching us.