Coverage does not finish and hangs at a certain number of tests

I am working on a large project that has several unit and integration tests for which we use NUnit and Resharper. When I run all the tests from the unit test explorer at a certain moment I get the message 'all unit tests are finished, but the test runner is still running'. If I choose to abort the test runner process, all the tests are green, and the number of tests equal the expected number. However, when I use the option 'cover unit tests' and want to run them all, it hangs at test 414 and I do not get the option to abort. Please help us here, as we have paid for a full license and we need to continue our work. We have Visual Studio 2019 latest update installed (not the preview) and also the latest resharper.