Failure to upgrade Ubuntu 20.04 "could not find a distribution template for Ubuntu/focal"

[David]

I tried to upgrade my Ubuntu using the Sofware Update interface app (as suggested by the app itself).

The app just fails to upgrade and suggests to use the bug-report, the logs show this error "could not find a distribution template for Ubuntu/focal" and another one about ubuntu-desktop being corrupted after the install.

Sorry if this is a bad report, I have no idea what is exactly failing.

Description: Ubuntu 20.04.6 LTS
Release: 20.04

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ubuntu-release-upgrader-core 1:20.04.41 [origin: unknown]
ProcVersionSignature: Ubuntu 5.4.0-162.179-generic 5.4.246
Uname: Linux 5.4.0-162-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu27.27
Architecture: amd64
CasperMD5CheckResult: skip
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Sun Sep 17 09:09:06 2023
InstallationDate: Installed on 2019-09-23 (1454 days ago)
InstallationMedia: Ubuntu 18.04.3 LTS "Bionic Beaver" - Release amd64 (20190805)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to focal on 2023-09-17 (0 days ago)
VarLogDistupgradeTermlog:

[Nick Rosbrook (enr0n)]

Reviewing the files from your upgrade attempt, you have installed pipewire packages from the pipewire-debian/pipewire-upstream PPA. Some of the packages installed are newer than those in the official archive, which is keeping some pipewire-related packages installed which then prevents the upgrade from being calculated. Please try using the ppa-purge tool to remove packages installed from ppa:pipewire-debian/pipewire-upstream by running ppa-purge -s ppa.launchpad.net -o pipewire-debian -p pipewire-upstream. After that you can try upgrading again and if it still fails open a new bug report. Thanks and good luck!

[David (david-cr96)]

Thank you so much for your help!
Sadly, ppa-purge fails :S

```
david@david-GS63-Stealth-8RD:~$ sudo ppa-purge -s ppa.launchpad.net ppa:pipewire-debian/pipewire-upstream
Updating packages lists
PPA to be removed: pipewire-debian pipewire-upstream
Warning: Could not find package list for PPA: pipewire-debian pipewire-upstream
```

EDIT: sorry, uploaded my second attempt, but result was the same for your exact command:
```
david@david-GS63-Stealth-8RD:~$ sudo ppa-purge -s ppa.launchpad.net -o pipewire-debian -p pipewire-upstream
Updating packages lists
PPA to be removed: pipewire-debian pipewire-upstream
Warning: Could not find package list for PPA: pipewire-debian pipewire-upstream
```