Diagnosis
The Hotkey Puck is either unpaired, out of battery, or its USB receiver is not properly connected.
How to Fix It
Check the connection. The Puck's USB receiver must be plugged into one of the monitor's USB downstream ports or directly into your computer. Replace the Puck's battery (CR2032). To re-pair, press and hold the pairing button on the USB receiver for 5 seconds, then press and hold the Back button on the Puck for 5 seconds until the LED flashes.
If That Didn't Work
The Puck may be configured for a different function profile. Open the BenQ Display Pilot software on your computer. Navigate to the Hotkey Puck settings and ensure the puck is detected and the button assignments are correct for the PD2706U.
Heads Up
The Hotkey Puck draws power constantly when in the dock. If not used regularly, remove it from the dock to conserve the battery.