RossKemp Discipline isn’t the same word as punishment.
What the OP is saying is that the previous discipline method is now not working.
Children do not stay the same in their responses to anything throughout their development.
OP, mine had some sort of havoc outbreak at about 4 or 5. I would advise loads of excercise: running races, jumping competitions.
Also lots of contact: tickles, play wrestle, tag, cuddles while rolling around, arm wrestle. So high energy moments amidst the endless craft and play doh and.... indoor lockdown stuff. Imaginative stuff for him to do, let him change his own environment; get a massive box big enough for him to be inside, let him transform it into anything g he wants, a den, space capsule canopy over his bed...
Wall paper or other massive paper: lie him on it and draw round him: let him decorate a life size version of him as whatever he likes and out it in his wall. Get him to think about what and who he loves and draw those in his head area.
And develop your firm and authoritative Voice . “I said no, I have explained why and that is the end of it”. “If you mess up my things your Lego will go in the cupboard and not come out for a week “. Grey rock any ‘don’t care!’ Stuff and follow through.
He is probably bored and frustrated, and any