I got this error when I was running pipeline on .Net6 core project made on VS2022. After changing pool vmimage to windows-2022 from windows-latest, things worked for me.
Reference MS Documentation
Also added latest version for Nugetinstalle
Nuget versions
steps:
 - task: NuGetToolInstaller@1
 inputs:
   versionSpec: '6.1'
   checkLatest: true
Now my pipeline looks like this,
trigger:
- master
pool:
  vmImage: 'windows-2022'
variables:
  solution: '**/*.sln'
  buildPlatform: 'Any CPU'
  buildConfiguration: 'Release'
steps:
- task: NuGetToolInstaller@1
  inputs:
    versionSpec: '6.1'
    checkLatest: true
- task: NuGetCommand@2
  inputs:
    restoreSolution: '$(solution)'
- task: VSBuild@1
  inputs:
    solution: '$(solution)'
    msbuildArgs: '/p:DeployOnBuild=true /p:WebPublishMethod=Package     /p:PackageAsSingleFile=true /p:SkipInvalidConfigurations=true /p:DesktopBuildPackageLocation="$(build.artifactStagingDirectory)\WebApp.zip" /p:DeployIisAppPath="Default Web Site"'
platform: '$(buildPlatform)'
configuration: '$(buildConfiguration)'