Why does not the lens pole of the Xiaomi Dual-mode Wireless Mouse 2 light up when turned on after being installed the battery?

The lens pole does not light up due to several reasons as follows:
1. The battery can not be properly installed, or the battery is depleted. Ensure the battery is placed correctly, and try a fresh one;
2. The mouse can not be switched on properly. Double-check the on/off switch to ensure the device is turned on;
3. The Xiaomi Dual-mode Wireless Mouse 2 uses an infrared light tracking engine to improve positioning accuracy and adapt to more desktops. At the same time, infrared light is almost invisible to the naked eye, and only a faint red light can be seen through the lens hole at the bottom.
If the issue persists, testing the mouse on different devices or checking for additional product details is necessary.