Result sending data OK even the client was not connected

[Igi54]

Hello, thank you for this very good library. But I have an issue. I have server and several clients. A client is connected. After a minute I disconnect the client by turning off power supply (so the client cannot send close). Now I send a data from server to the client which was disconnected. But I the result of the sending data is OK. But it could not been sent because physically the client is not connected anymore. How to please fix it? Thank you in advance.