You have multiple metapackages installed and this can cause issues with the release upgrader being able to calculate the upgrade path.
2020-05-09 11:09:54,947 DEBUG MetaPkgs: kubuntu-desktop ubuntu-desktop ubuntu-mate-core ubuntu-mate-desktop xubuntu-core xubuntu-desktop You might want to try removing some of the metapackages and try the upgrade again. ** Summary changed: - fail to upgrade + fail to upgrade due to multiple metapackages installed ** Changed in: ubuntu-release-upgrader (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1877722 Title: fail to upgrade due to multiple metapackages installed To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1877722/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs