You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I am planning to visit Downtown Aquarium at Houston, could you please help me with booking a flight ticket from SEA to HOU?

ASSISTANT: Please share your travelling dates.

USER: I would like to depart on Sept 15th and return on Sept 17th.

ASSISTANT: Do you need any connection limit?

USER: I need a flight with single stopover.

ASSISTANT: May I know your name?

USER: I am Shirley Lopez.

ASSISTANT: Do you have any specifications?

USER: I need a flight ticket in economy class. And make sure that my depart time must be afternoon.

ASSISTANT: Please wait.

USER: Sure, take your time.

ASSISTANT:  Sorry, no flights are available with your requirements.

USER: Ok, not an issue. Anyways, thank you for the information.

ASSISTANT: Thank you for choosing us.