Tighten the screws on the knob or handle plate
Remove the cover plate if needed to access hidden screws
Check both sides of the door knob for loose hardware
Tighten the set screw on the knob if present
Replace stripped or damaged screws with new ones
Use longer screws if the existing ones will not hold
Realign the latch mechanism if the knob still wobbles
Inspect the spindle and replace it if worn or broken
Reattach any loose interior trim or mounting plate
Test the knob after tightening to confirm it is secure