Forgetting a Wi-Fi network is a helpful step in troubleshooting issues with your network connection. Forgetting a network will not prevent you from connecting to it in the future, though you may be asked to reenter your credentials.
Mac OS
NOTE: You will need administrator rights to your machine to perform this action.
Open System Preferences.
Click Network.
Uncheck Automatically join this network.
Click Advanced.
Highlight the Network you want to forget.
Click the Minus (-) button.
Windows 10
Click the Network icon from the taskbar.
Right-click the Network to forget.
Click Forget from the drop-down.
iOS (iPhone and iPad)
Navigate to Settings.
Tap Wi-Fi.
Tap the info button next to the network you want to forget.
Tap Forget This Network.
Android OS
Slide the Quick Settings Drop-Down menu from the top of the screen.
Tap the gear icon from the top right of the screen.