Freezer Door opens/rattles if Refrigerator Door is opened or closed
Door can rattle due to air pressure inside (cold air circulation).
Refrigerator is designed so that air can circulate between the freezer and the refrigerator
Therefore closing the Refrigerator door with a strong force can make the Freezer door to
rattle or open slightly and close back.
How to fix
This phenomenon is normal and not a defect of the product.
Low adherence of rubber gasket can also cause door to rattle. Clean the rubber gasket.
If the problem persists, level the product so that it inclines slightly to the back.