My dock dissappear

This happened to me too. I tried recommended fixes I found on DDG but none of them worked. After some trial and error I found this solution worked permanently.

1. Got to System Preferences > Keyboard > Shortcuts > Launchpad & Dock
2. Turn off 'Turn Dock Hiding On/Off'
3. Go to System Preferences > Dock
4. Untick 'Automatically hide and the show Dock'

If this does not solve the issue, leave the amended settings as they are and restart your computer.

If this does not work, then go back to Systems Preferences and reset the settings above as they were making any changes. Then restart and make the same changes listed above but in this order:

1. Go to System Preferences > Dock
2. Untick 'Automatically hide and the show Dock'
3. Got to System Preferences > Keyboard > Shortcuts > Launchpad & Dock
4. Turn off 'Turn Dock Hiding On/Off'