Use a small amount of high-percentage Isopropyl Alcohol on a cotton swab and click the Volume Down button repeatedly to clear any debris.
Ensure it matches your specific model number (found on the bottom of the device or the original box).
A stuck Volume Down button can force the device into the bootloader every time it restarts. Step 1: The "Hard Reset" Escape blackberry keyone stuck in bootloader menu repack
BlackBerry devices are notoriously picky about USB cables. Use the original USB-C cable and a USB 2.0 port if possible.
Getting your BlackBerry KEYone out of a bootloader loop usually requires returning to basics: a clean, official Autoloader and a stable USB connection. Avoid "repacks" from unverified sources, as these often lack the necessary signatures to pass the KEYone's secure boot check. Use a small amount of high-percentage Isopropyl Alcohol
Stuck in the Bootloader: A Comprehensive Guide to Fixing and Repacking Your BlackBerry KEYone
If your terminal window shows errors like remote: partition table doesn't exist or writing 'system' failed , try these steps: Step 1: The "Hard Reset" Escape BlackBerry devices
If you have successfully flashed a clean Autoloader and the device still returns to the bootloader menu, you likely have a hardware fault.
Connect your KEYone to the PC while it is on the bootloader screen. Run the flashall.bat (Windows) or flashall.sh (Linux/Mac) file from your Autoloader folder.
If the device vibrates and shows the BlackBerry logo, release the buttons. Step 2: Verifying Your "Repack" or Autoloader