• Ensure that the Liquibase repository is correctly added to the apt sources list. You can verify this by examining the contents of the cat /etc/apt/sources.list.d/liquibase.list file.

• This should display a line similar to:

  deb [arch=amd64 signed-by=/usr/share/keyrings/liquibase-keyring.gpg] https://repo.liquibase.com stable main

• If the line is missing or incorrect, you may need to re-add the repository following Install Liquibase on Linux with Debian or Ubuntu.

Before attempting to install Liquibase again, make sure to update the package lists using: sudo apt-get update

This ensures that apt has the latest information about available packages.

After updating the package lists, attempt to install Liquibase again with the install article.