ASP.NET Core 2.1 - NuGet - Blocked by project issue - AspnetCore.App

Some NuGet packages are added by default as part of framework.

https://docs.microsoft.com/en-us/nuget/tools/package-manager-ui#updating-a-package

For example : Microsoft.ASPNetCore.App.

If you get error that you can not update them to newest version with something like:
"Blocked by project. Update SDK"
; this could help.

Opet CSPROJ file and manually add this line under <PropertyGroup>:

<RuntimeFrameworkVersion>2.1.4</RuntimeFrameworkVersion>