Diagnosis
The Auto Pivot sensor or software handshake is inactive. It requires both hardware recognition and correct driver/software on your computer.
How to Fix It
First, ensure the feature is enabled in the monitor OSD. Press the joystick, go to System > Auto Pivot, set it to On. You must have the BenQ Display Pilot software installed on your connected computer. The software must be running and have the correct permissions to detect orientation changes.
If That Didn't Work
The monitor's G-Sensor may need recalibration. In the OSD, navigate to System > Auto Pivot and select G-Sensor Calibration. Follow the on-screen instructions to lay the monitor flat and then upright.
Heads Up
Auto Pivot primarily functions over the USB-C connection. It may not work reliably over HDMI or DisplayPort, even with the USB-B cable connected for peripheral data.