Removing Dye Transfer on Colored Clothing

I tried cleaning a food spot from an expensive cotton sweatshirt, which is dark blue with a wide yellow stripe. The spot was on the yellow stripe, which has a dark blue backing. The blue bled onto the yellow. Washing instructions say the shirt can be washed in cold water and dried flat. Does anyone have any idea how I can remove the stain? Thank you.

By Evelyn from Sunnyvale, CA