Review on 🎮 REDSTORM Pro Controller for Nintendo Switch, Christmas Present: Bluetooth Wireless Gamepad Joystick Joypad, Turbo/Double Vibration/6-Axis, Compatible with Switch, Switch Lite, and Switch OLED - Yellow Dragon by Cameron Chandra

Found in FAQ: Slightly modified - How do I connect the controller to the switch? Start the switch. Go to controller setup. , press and hold it, the indicators flash quickly for 5 seconds, the LED indicator is still on, the connection is successful. It works out!