White marks have more than one possible cause
Manufacturer troubleshooting guidance lists excess detergent, lint, non-HE detergent in an HE washer, water conditions, temperature and washer buildup among possible causes. That is why simply adding another wash chemical is not a reliable diagnosis.
If the marks look like detergent clumps
Rewash the affected items without adding extra detergent and verify the product dose and washer compatibility. Powdered detergents can be more sensitive to dissolving conditions.
If the marks look like lint
Consider what was washed together. New towels and other lint-producing items can leave visible fibers on dark or lint-attracting garments.
If the problem keeps returning
Check load size, cycle selection, detergent type and the washer's cleaning instructions. Repeated residue across unrelated loads may point to a machine or process issue rather than one garment.
Garment care labels, appliance manuals and laundry-product directions can be more specific than a general guide. Use them when they set a tighter limit.