You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Dennis Lopez.

ASSISTANT: How can I help you today?

USER: I have a plan to meet my childhood friend in Detriot, can you help me for booking a flight ticket?

ASSISTANT: Sure, I am glad to help you. Can you please share your planning dates of journey?

USER: My travelling dates are from 10/21 till 10/23.

ASSISTANT: Ok, may I know your airport codes?

USER: My travelling airport codes are from SEA to DTW.

ASSISTANT: Sorry, no flights are available on your route.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.