Maybe its an defency of k?

not enough info or weeks to see the progression in diary.. your defoliation probably exacerbated it. you only have small leaves all over... this is not ideal.

Honestly since your leaves are curling up at the ends and it’s happening all over I’m thinking it’s a phosphorus deficient. Potassium the leaves curl down and the death happens up the edges of the leaf and not the tips. Hope this helps.