What you're describing, white-bordered patches that move around and heal on their own, matches geographic tongue. It's a harmless condition and not an infection, so a year of multivitamins not fixing it is actually expected, there's nothing for them to cure.
Next Steps
It won't turn into anything serious later, it doesn't spread or affect your general health. Spicy, sour or very hot food can make a flare feel worse, so easing up on those during an episode helps.
Health Tips
Please see a dentist or physician in person if a patch ever stays fixed in one spot for weeks, grows, or becomes very painful, so other causes can be ruled out.