Bleach isn't working. :0|
throw it out.
Fels Naptha laundry soap bar, or white Dial bar soap works for stains as well.
https://www.amazon.com/Fels-Naptha-Laundry-Stain-Remover/dp/B0063KX...
Bleach
Sometimes you can't ... Try a soaking solution ... also your deoderant may be the cause
Change deodorant brands.
It´s really hard to remove those stains.
White dye
You can use a search engine. I use Fels Naptha. The bar is huge and lasts a long long time using it just for stains. White Dial is a real close second.
Then you are screwed. How about dying the shirt a different colour?
hahahaha.. If you like, you can always have a little taste while doing the chore..
Treat yourself to some new shirts, then wear undershirts when you put them on.
Then wear yellow more often :-)
Start using white cheese on those sandwiches.