How to Lock the Bootloader on SAMSUNG Galaxy A72: Step-by-Step Guide

Preparing Your Galaxy A72 for Bootloader Relocking

• ⚠️ Back up all important data before proceeding, as locking the bootloader will erase your phone.
• 🔐 Remove your Google account from Settings > Accounts and backup > Manage account to avoid Factory Reset Protection (FRP) issues.
• 📶 Ensure you are connected to a Wi-Fi network.

Accessing Developer Options and Bootloader Mode

• 📱 Navigate to Settings > About phone > Software information and tap the Build number seven times to enable Developer options.
• ⚙️ In Developer options, you should see OEM unlocking enabled if the bootloader is currently unlocked.
• 🔌 To enter bootloader mode, power off the phone, then press and hold Volume Up + Volume Down while plugging in a USB-C cable connected to a computer.

Relocking the Bootloader and Factory Reset

• 🔒 On the blue screen, press and hold Volume Up to confirm the 'Lock bootloader' action, which will initiate a factory reset.
• ⏳ The phone will erase data and restart, requiring you to go through the initial setup process.

Post-Reset Configuration and Security

• 🌐 After setup, connect to your Wi-Fi network.
• 🛠️ Re-access Developer options by tapping the Build number seven times again.
• 🚫 Disable OEM unlocking in Developer options to ensure the bootloader remains locked and protected.
• 🔄 Restart your phone to finalize the process.