You can reset your password following the next steps:
- Reboot your computer / Turn your computer on.
- Hold down the Shift key at the start of the boot process to enable the GNU GRUB boot menu (if it does not show)
- Press ESC at the GNU GRUB prompt.
- Press e for edit.
- Use the Arrow keys to highlight the line that begins with kernel and press the e key.
- Go to the very end of the line and add
rw init=/bin/bash
- Press Enter and then press b to boot your system.
- Your system will boot up to a passwordless root shell.
- Type in
passwd yourusername
- Set your new password.
- Restart your system
