An existing dotNet core 2.0 solution was working fine with dotCover. I added a new project and a new test project for it but dotCover is not working for this new one. It just does not show any coding covered or percentage.
The test project was created after upgrading Visual Studio to 2019 and it used the new Dotnet core 3.0 instead of 2.0. After aligning the versions the issue was solved.