When Wi-Fi Direct (Simple AP) connection disabled, all computers and smart devices connected to the printer in Wi-Fi Direct (Simple AP) connection are disconnected. If you want to disconnect a specific device, disconnect from the device instead of the printer.
Select Wi-Fi on the printer's home screen.
To select an item, use the 
buttons, and then press the OK button.
Select Wi-Fi Direct.
The Wi-Fi Direct information is displayed.
Press the OK button.
Select 
.
Select Disable Wi-Fi Direct.
Follow the on-screen instructions.