a package is not found

The package that you are trying to download has already been superseded by a new version (2.9.14+dfsg-1.3ubuntu3.3 instead of 2.9.14+dfsg-1.3ubuntu3.2; fixing CVE-2025-32414 and CVE-2025-32415)

Try the following commands

sudo apt update
sudo apt full-upgrade

and report the results.

sudo apt update
[sudo] password for bakai:
Get:1 http://security.ubuntu.com/ubuntu noble-security InRelease [126 kB]
Hit:2 http://archive.ubuntu.com/ubuntu noble InRelease
Get:3 https://dl.google.com/linux/chrome/deb stable InRelease [1,825 B]
Hit:4 https://ppa.launchpadcontent.net/dotnet/backports/ubuntu noble InRelease
Hit:5 https://download.docker.com/linux/ubuntu noble InRelease
Get:6 https://dl.google.com/linux/chrome/deb stable/main amd64 Packages [1,213 B]
Hit:7 https://packages.microsoft.com/repos/code stable InRelease
Hit:8 https://repo.waydro.id noble InRelease
Hit:9 https://download.sublimetext.com apt/stable/ InRelease
Get:10 http://security.ubuntu.com/ubuntu noble-security/main amd64 Components [21.5 kB]
Get:11 http://security.ubuntu.com/ubuntu noble-security/restricted amd64 Components [208 B]
Get:12 http://security.ubuntu.com/ubuntu noble-security/multiverse amd64 Components [208 B]
Get:13 http://security.ubuntu.com/ubuntu noble-security/universe amd64 Components [52.2 kB]
Fetched 203 kB in 2s (87.3 kB/s)
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
1 package can be upgraded. Run 'apt list --upgradable' to see it.
 ~  sudo apt full-upgrade
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Calculating upgrade... Done
Get more security updates through Ubuntu Pro with 'esm-apps' enabled:
  vlc-plugin-qt libvlc5 libzvbi-common vlc-data libvlccore9 vlc vlc-bin
  vlc-l10n libcjson1 libavdevice60 ffmpeg libpostproc57 vlc-plugin-samba
  libavcodec60 libzvbi0t64 vlc-plugin-notify libavutil58 libswscale7
  vlc-plugin-access-extra vlc-plugin-skins2 vlc-plugin-video-splitter
  libswresample4 vlc-plugin-video-output libavformat60 libvlc-bin
  vlc-plugin-base vlc-plugin-visualization libavfilter9
Learn more about Ubuntu Pro at https://ubuntu.com/pro
The following packages will be upgraded:
  python3-libxml2
1 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 standard LTS security update
Need to get 139 kB of archives.
After this operation, 1,024 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Err:1 http://security.ubuntu.com/ubuntu noble-security/universe amd64 python3-libxml2 amd64 2.9.14+dfsg-1.3ubuntu3.2
  404 Not Found [IP: 91.189.91.82 80]
E: Failed to fetch http://security.ubuntu.com/ubuntu/pool/universe/libx/libxml2/python3-libxml2_2.9.14%2bdfsg-1.3ubuntu3.2_amd64.deb 404 Not Found [IP: 91.189.91.82 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

What output do you receive for the command

apt policy python3-libxml2

apt policy python3-libxml2
python3-libxml2:
  Installed: 2.9.14+dfsg-1.3ubuntu3
  Candidate: 2.9.14+dfsg-1.3ubuntu3.2
  Version table:
     2.9.14+dfsg-1.3ubuntu3.2 500
        500 http://security.ubuntu.com/ubuntu noble-security/universe amd64 Packages
 *** 2.9.14+dfsg-1.3ubuntu3 500
        500 http://archive.ubuntu.com/ubuntu noble/universe amd64 Packages
        100 /var/lib/dpkg/status

This is strange. On my system I see the 2.9.14+dfsg-1.3ubuntu3.3 version as candidate.

Try forcing a reload of the package inventory by executing these commands:

sudo rm -rf /var/lib/apt/lists/*
sudo apt update
apt policy python3-libxml2

and copy/paste the output as done before.

It worked now. Thank you very much!

sudo rm -rf /var/lib/apt/lists/*
sudo apt update
apt policy python3-libxml2
[sudo] password for bakai:
Get:1 http://security.ubuntu.com/ubuntu noble-security InRelease [126 kB]
Get:2 http://archive.ubuntu.com/ubuntu noble InRelease [256 kB]
Get:3 https://dl.google.com/linux/chrome/deb stable InRelease [1,825 B]
Get:4 https://download.docker.com/linux/ubuntu noble InRelease [48.8 kB]
Get:5 https://dl.google.com/linux/chrome/deb stable/main amd64 Packages [1,214 B]
Get:6 https://ppa.launchpadcontent.net/dotnet/backports/ubuntu noble InRelease [24.1 kB]
Get:7 https://download.sublimetext.com apt/stable/ InRelease [2,536 B]
Get:8 https://download.docker.com/linux/ubuntu noble/stable amd64 Packages [24.0 kB]
Get:9 https://repo.waydro.id noble InRelease [1,309 B]
Get:10 https://packages.microsoft.com/repos/code stable InRelease [3,590 B]
Get:11 https://ppa.launchpadcontent.net/dotnet/backports/ubuntu noble/main amd64 Packages [5,864 B]
Get:12 https://ppa.launchpadcontent.net/dotnet/backports/ubuntu noble/main Translation-en [2,284 B]
Get:13 http://security.ubuntu.com/ubuntu noble-security/main i386 Packages [270 kB]
Get:14 https://download.sublimetext.com apt/stable/ Packages [9,890 B]
Get:15 https://repo.waydro.id noble/main all Packages [2,283 B]
Get:16 http://archive.ubuntu.com/ubuntu noble/main i386 Packages [1,041 kB]
Get:17 https://packages.microsoft.com/repos/code stable/main arm64 Packages [19.5 kB]
Get:18 http://security.ubuntu.com/ubuntu noble-security/main amd64 Packages [782 kB]
Get:19 https://packages.microsoft.com/repos/code stable/main armhf Packages [19.6 kB]
Get:20 https://packages.microsoft.com/repos/code stable/main amd64 Packages [19.2 kB]
Get:21 http://archive.ubuntu.com/ubuntu noble/main amd64 Packages [1,401 kB]
Get:22 http://archive.ubuntu.com/ubuntu noble/main Translation-en [513 kB]
Get:23 http://archive.ubuntu.com/ubuntu noble/main amd64 Components [464 kB]
Get:24 http://archive.ubuntu.com/ubuntu noble/main Icons (48x48) [106 kB]
Get:25 http://archive.ubuntu.com/ubuntu noble/main Icons (64x64) [156 kB]
Get:26 http://archive.ubuntu.com/ubuntu noble/main Icons (64x64@2) [21.8 kB]
Get:27 http://archive.ubuntu.com/ubuntu noble/main amd64 c-n-f Metadata [30.5 kB]
Get:28 http://archive.ubuntu.com/ubuntu noble/restricted i386 Packages [14.7 kB]
Get:29 http://archive.ubuntu.com/ubuntu noble/restricted amd64 Packages [93.9 kB]
Get:30 http://archive.ubuntu.com/ubuntu noble/restricted Translation-en [18.7 kB]
Get:31 http://archive.ubuntu.com/ubuntu noble/restricted amd64 c-n-f Metadata [416 B]
Get:32 http://archive.ubuntu.com/ubuntu noble/universe i386 Packages [8,514 kB]
Get:33 http://archive.ubuntu.com/ubuntu noble/universe amd64 Packages [15.0 MB]
Get:34 http://archive.ubuntu.com/ubuntu noble/universe Translation-en [5,982 kB]
Get:35 http://archive.ubuntu.com/ubuntu noble/universe amd64 Components [3,871 kB]
Get:36 http://archive.ubuntu.com/ubuntu noble/universe Icons (48x48) [3,717 kB]
Get:37 http://archive.ubuntu.com/ubuntu noble/universe Icons (64x64) [7,747 kB]
Get:38 http://archive.ubuntu.com/ubuntu noble/universe Icons (64x64@2) [75.0 kB]
Get:39 http://archive.ubuntu.com/ubuntu noble/universe amd64 c-n-f Metadata [301 kB]
Get:40 http://archive.ubuntu.com/ubuntu noble/multiverse amd64 Packages [269 kB]
Get:41 http://archive.ubuntu.com/ubuntu noble/multiverse i386 Packages [126 kB]
Get:42 http://archive.ubuntu.com/ubuntu noble/multiverse Translation-en [118 kB]
Get:43 http://archive.ubuntu.com/ubuntu noble/multiverse amd64 Components [35.0 kB]
Get:44 http://archive.ubuntu.com/ubuntu noble/multiverse Icons (48x48) [56.1 kB]
Get:45 http://archive.ubuntu.com/ubuntu noble/multiverse Icons (64x64) [186 kB]
Get:46 http://archive.ubuntu.com/ubuntu noble/multiverse Icons (64x64@2) [904 B]
Get:47 http://archive.ubuntu.com/ubuntu noble/multiverse amd64 c-n-f Metadata [8,328 B]
Get:48 http://security.ubuntu.com/ubuntu noble-security/main Translation-en [147 kB]
Get:49 http://security.ubuntu.com/ubuntu noble-security/main amd64 Components [21.5 kB]
Ign:49 http://security.ubuntu.com/ubuntu noble-security/main amd64 Components
Get:50 http://security.ubuntu.com/ubuntu noble-security/main Icons (48x48) [13.4 kB]
Get:51 http://security.ubuntu.com/ubuntu noble-security/main Icons (64x64) [20.0 kB]
Get:52 http://security.ubuntu.com/ubuntu noble-security/main Icons (64x64@2) [29 B]
Get:53 http://security.ubuntu.com/ubuntu noble-security/main amd64 c-n-f Metadata [7,068 B]
Get:54 http://security.ubuntu.com/ubuntu noble-security/restricted amd64 Packages [931 kB]
Get:55 http://security.ubuntu.com/ubuntu noble-security/restricted i386 Packages [15.6 kB]
Get:56 http://security.ubuntu.com/ubuntu noble-security/restricted Translation-en [191 kB]
Get:57 http://security.ubuntu.com/ubuntu noble-security/restricted amd64 Components [208 B]
Get:58 http://security.ubuntu.com/ubuntu noble-security/restricted Icons (48x48) [29 B]
Get:59 http://security.ubuntu.com/ubuntu noble-security/restricted Icons (64x64) [29 B]
Get:60 http://security.ubuntu.com/ubuntu noble-security/restricted Icons (64x64@2) [29 B]
Get:61 http://security.ubuntu.com/ubuntu noble-security/restricted amd64 c-n-f Metadata [468 B]
Get:62 http://security.ubuntu.com/ubuntu noble-security/multiverse i386 Packages [2,896 B]
Get:63 http://security.ubuntu.com/ubuntu noble-security/multiverse amd64 Packages [17.6 kB]
Get:64 http://security.ubuntu.com/ubuntu noble-security/multiverse Translation-en [3,792 B]
Get:65 http://security.ubuntu.com/ubuntu noble-security/multiverse amd64 Components [208 B]
Get:66 http://security.ubuntu.com/ubuntu noble-security/multiverse Icons (48x48) [29 B]
Get:67 http://security.ubuntu.com/ubuntu noble-security/multiverse Icons (64x64) [29 B]
Get:68 http://security.ubuntu.com/ubuntu noble-security/multiverse Icons (64x64@2) [29 B]
Get:69 http://security.ubuntu.com/ubuntu noble-security/multiverse amd64 c-n-f Metadata [380 B]
Get:70 http://security.ubuntu.com/ubuntu noble-security/universe i386 Packages [515 kB]
Get:71 http://security.ubuntu.com/ubuntu noble-security/universe amd64 Packages [833 kB]
Get:72 http://security.ubuntu.com/ubuntu noble-security/universe Translation-en [181 kB]
Get:73 http://security.ubuntu.com/ubuntu noble-security/universe amd64 Components [52.2 kB]
Get:74 http://security.ubuntu.com/ubuntu noble-security/universe Icons (48x48) [45.0 kB]
Get:75 http://security.ubuntu.com/ubuntu noble-security/universe Icons (64x64) [70.7 kB]
Get:76 http://security.ubuntu.com/ubuntu noble-security/universe Icons (64x64@2) [29 B]
Get:77 http://security.ubuntu.com/ubuntu noble-security/universe amd64 c-n-f Metadata [17.0 kB]
Get:49 http://security.ubuntu.com/ubuntu noble-security/main amd64 Components [21.5 kB]
Fetched 54.6 MB in 5min 19s (171 kB/s)
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
10 packages can be upgraded. Run 'apt list --upgradable' to see them.
python3-libxml2:
  Installed: 2.9.14+dfsg-1.3ubuntu3
  Candidate: 2.9.14+dfsg-1.3ubuntu3.3
  Version table:
     2.9.14+dfsg-1.3ubuntu3.3 500
        500 http://security.ubuntu.com/ubuntu noble-security/universe amd64 Packages
 *** 2.9.14+dfsg-1.3ubuntu3 500
        500 http://archive.ubuntu.com/ubuntu noble/universe amd64 Packages
        100 /var/lib/dpkg/status

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