Unintentional double-clicking is caused by a worn-out mouse switch or incorrect OS settings. First, check your settings: on Windows go to Settings > Bluetooth & devices > Mouse and make sure the double-click speed slider isn't set too slow. On Mac, go to System Settings > Accessibility > Pointer Control and check the double-click speed. If settings are fine, the switch itself is wearing out — this is common after 1-2 years of heavy use. As a temporary fix, increase the double-click speed in settings so the system waits less time between clicks. You can also install mouse debounce software that ignores clicks within a short interval. For a permanent fix on mechanical switch mice, the switch can be replaced with a soldering iron (common repair for gaming mice). If the mouse is under warranty, contact the manufacturer for replacement.