Hello,
I understand your problem.
See as we age, our skin also age and become dull it has many reasons for dullness of skin.
as per your history you are taking multivitamins supplements and using sunscreen. they are good but you will need combination treatments for satisfactory results for your issue.
you will need combination treatments like chemical peels, botox, fillers, threads, micro needling
Next Steps
Please visit nearest facial cosmetic surgeon for your issues.