Hi there, With plants in general damaged leaves will not recover, so don't expect them to turn back again to normal. Once there is more new growth, i would just remove the old damaged ones, and of course first check with the new growth that the problems have disappeared.
How much nutrients did you use? Do you have an EC meter for testing?
If you're in soil, I suggest reading this link: https://www.mandalaseeds.com/Guides/Fertilizing-Smart-Guide
happy growing