As stated by @PanagiotisKanavos C# Dec Kit does not have support for any Dot Net version below 7, my work around was to use a windows VM (my main system runs linux) with Visual Studio 2019 installed to implement the feature and debug the code.

I should mention that I can run the code perfectly fine using Linux it's just the lack of any debugging tools for that version so you have to write to the console to see what's happening.

The version used in the project should be updated though but that's not my call to make. ̄\_ (ツ)_/ ̄