Continue holding until you see a screen with "Screen Display Test" or a white/green menu list. Release the keys.
Use the Volume Down (-) key to scroll down until you find: "Clear eMMC" or "Factory Reset" Note: On some firmware versions, it is labeled "Clear Storage." How to Hard Reset NOKIA 5310 2020 Dual SIM
Ensure the battery has at least 30% charge to avoid shutting down during the process. Continue holding until you see a screen with