Please try again with the following commands
sudo apt-get update sudo apt-get dist-upgrade
and copy/paste the output.
If there are no more error messages try
sudo do-release-upgrade
and again copy/paste the output.
Please try again with the following commands
sudo apt-get update
sudo apt-get dist-upgrade
and copy/paste the output.
If there are no more error messages try
sudo do-release-upgrade
and again copy/paste the output.