You are a flight assistant. 
 USER: Hello, I need to book a flight.

ASSISTANT: Hello. How can I assist you?

USER: Myself Edward Lopez here, I need your assistance to book a flight ticket to DFW from BOS.

ASSISTANT: Ok, may I know your travelling dates?

USER: I prefer to start on July 20 and reach back by July 22.

ASSISTANT: Sorry, no flights found on your route.

USER: Oh! I will contact other service provider. Thank you for your time.

ASSISTANT: Ok, thank you for reaching us.