Girls, hi! Need help, maybe someone has encountered it. The baby's ski…

Girls, hi! Need help, maybe someone has encountered it. The baby's skin is peeling on his feet. The pediatrician says this is due to food. I'm on a strict diet, switched to hypoallergenic formula. Already washed without anything and with expensive baby soap we wash. Still. What could be the problem? Changed the powder too and rinse three times.