Exchanges consider your account dormant and deactivate it when there is no trading activity for 24 consecutive months. You need to verify your KYC details to reactivate your account.
If you do not reactivate your account within 30 days, Zerodha notifies your nominee(s). The nominee can notify or claim shares after the death of a Zerodha account holder. To learn why it is important for the nominee(s) to be aware, see Introducing online nomination.