Upgrade from 18.04 to 20.04

[Krishnaiah Marichetty]

Error: No minimal package available

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.42
ProcVersionSignature: Ubuntu 4.15.0-135.139-generic 4.15.18
Uname: Linux 4.15.0-135-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.23
Architecture: amd64
CrashDB: ubuntu
Date: Sat Feb 13 17:29:32 2021
InstallationDate: Installed on 2017-07-27 (1297 days ago)
InstallationMedia: Ubuntu 16.04.2 LTS "Xenial Xerus" - Release amd64 (20170215.2)
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_IN:en
 TERM=linux
 PATH=(custom, no user)
 LANG=en_IN
 SHELL=/bin/bash
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2021-02-13 (0 days ago)
VarLogDistupgradeAptlog:
 Log time: 2021-02-13 17:28:30.641874
 Log time: 2021-02-13 17:28:48.022644
 Log time: 2021-02-13 17:29:27.648150
 Log time: 2021-02-13 17:29:40.545261
VarLogDistupgradeTermlog: