Your garment is made with a technical compression fabric. To keep the stretch and the compression it left the factory with, always wash it with like colors and follow these instructions.
Fabric softener and bleach break down the elastic fibres, and those fibres are the compression. A faja washed with softener stops compressing long before it should. Heat, from an iron or from a hot wash, does the same thing.
If you wear one every day, it is worth having two: one on, one in the wash. That way neither one sits damp for hours or gets worn several days in a row.
