If your newer top canopy looks nice an healthy I wouldn’t worry about it, if you did have a deficiency of some sort it’s been fixed now Also how close have you got your lights could be a sign of heat stress by the looks of your leaves slightly curling upwards either that or over watering... with saying all that I am new to growing myself just giving you a few hints a what you’re problem could be hope someone answers youre question abit more precise for you haha happy growing good luck 👌🏻✌️🏻