Rider doesn't recognise Unity has started with Code Coverage

Hello, I hope I'm posting this on the correct topic.

I am trying to get code coverage to work on my Unity project, but after following the following steps:

• Open my project on Rider
• Select 'Start Unity (2018.4.13f1) with Coverage'

When I try to run any tests with coverage, I get prompted with the same message:

"To run code coverage analysis, restart Unity Editor using the 'Start Unity with Coverage' action on the Unity toolbar."

I've tried updating Rider and restarting my computer but nothing works.

I tested this on a different project and it works, so apparently there's something wrong with my Unity project?

Would be great if I could get some help on this. I am really excited to test this feature.