You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how can I serve you today?

USER: I planned baby shower program with my family at Washington DC-DCA on 12/02.

ASSISTANT: May I know your origin and return day?

USER:  I should return on 12/04 from PHL.

ASSISTANT: Please wait for a minute, I will check the availability of flights and let you know.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry to inform you that unfortunately there is no flights available on the given days.

USER: Ok, thank you.

ASSISTANT: Thank you for availing with us.