Sometimes the issue is not mechanical, but a setting that has been changed or misconfigured.

You move your finger across the smooth glass top, but the page stays frozen. No vertical movement. No horizontal glide. Just a cursor that moves fine, but a scroll wheel that has seemingly vanished.

Restart your Mac. Your settings will revert to default, and scrolling should be restored. 7. Check for Hardware Contamination

Unlike traditional mice with a wheel, the Magic Mouse uses a on the top surface. Oil, dead skin, or residue creates "dead spots."