How do I permanently delete my PSN account?
Tap Account & Security. Choose Account Management. Select Create, change and close account. Tap How to close your account for PlayStation™Network.
How do I permanently delete a user on PS4?
PlayStation 4
you can make a new one but you'll lose everything [trophies, purchases, funds] tied to your old account. you can keep the same email if you wish, but you have to first change the email of the old account to free up that email address for use on the new account.