i can't update ubuntu 20.04 to 21.10

[Benjamin Salazar Angeles]

the warning sed me that i have no official Ubuntu package and that this command <<ppa-purge>> solve the problem, but it didn't.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ubuntu-release-upgrader-core 1:20.04.37
ProcVersionSignature: Ubuntu 5.13.0-35.40~20.04.1-generic 5.13.19
Uname: Linux 5.13.0-35-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.21
Architecture: amd64
CasperMD5CheckResult: skip
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Thu Mar 17 23:18:38 2022
InstallationDate: Installed on 2020-12-17 (455 days ago)
InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to focal on 2022-03-18 (0 days ago)
VarLogDistupgradeTermlog:

modified.conffile..etc.update-manager.release-upgrades: [modified]
mtime.conffile..etc.update-manager.release-upgrades: 2022-02-15T22:50:53.388131