You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Samuel Mitchell.

ASSISTANT: What service do you need from our travel agency?

USER: Can you do some guidance in flight ticket booking from IAD to DTW?

ASSISTANT: Ok, can you please help me by providing the travel dates?

USER: Thank you and my dates are on 07/21 and back on 07/23 and search for a direct flight.

ASSISTANT: Sorry to inform you, there are no flights running on the dates you have given.

USER: Ok, no problem, I can reach another agency to book my flight ticket.

ASSISTANT: You are welcome. Thank you for reaching our travel agency.

USER: Most welcome and have a nice day.