I am unable to scaffold an API Controller with CRUD using DBContext in Visual Studio 2019 ver 16.xx

When I select the option to add an API Controller. I get an error saying

"There was an error running the selected Code Generator. Package restore failed. Rolling back changes for the project xxx"

I have tried to add the Entity Framework Core Nuget packages, namely EntityFrameworkCore, EntityFrameworkCore.Design and EntityFrameworkCore.SqlServer already. Attempt to do the same operation using CLI also did not work. Any help or assistance to fix or troubleshoot this further would be appreciated.