I didn’t find the black stains on my red sweater until the next day after I had washed AND dried, so the stain is probably really set in there. I washed with cold water so the black wouldn’t bleed, but I didn’t think about the dryer and set it at a high temperature.

I read online that stains that have been set in after drying can be removed with persistence, but I can’t find any solutions that fit my specific case. I don’t want to use bleach because my sweater is red. What should I do?