Yes! It can be fixed!
For white or light colored tops with yellowing pit stains here is what you’ll need:
A rectangular plastic tub
A small dish or yogurt container for mixing
A spoon for mixing
An old tooth brush
Get out those tees and tops with yellowing pit stains!
Mix together equal parts hydrogen peroxide, baking soda and dish soap in the yogurt dish until it’s an easy-to-stir, bubbly paste.
Use the spoon to apply the paste to the interior and exterior of the pit stain.
Use the tooth brush to scrub it in and loosen the buildup of deodorant residue.
Let sit overnight in your plastic tub (or for a day or so).
Wash on warm as normal. I suggest washing these treated tees separately or with other whites so you don’t accidentally bleach your other clothing
Don’t wash on “hot”- this can break down and erode your clothing, warm is plenty to get that soap activated.
Dry for about 10-15 minutes, then hang. This will allow all the wrinkles to release but save the fabric from the beating of the dryer.