To fix this problem, you must go to your files where your configurations are stored. This is done by opening the archive explorer, and going to (NAME)/AppData/LocalLow/Steelraven7/RavenfieldSteam/GameConfigurations
Then, once you have located the configurations, the files should appear like this:
If you try to open the file, it will tell you what to open it with. I have chosen wordpad, but you can choose whatever you want, like a coding program.
You will be greeted by a popup that shows the code of the configuration, that will most likely look similar to this.


After that, simply scroll down until you find the mutator section, which looks like this.

To fix the mutators, simply change the commas in the values to dots.
Once that is done, save the file. If you have followed the steps correctly, your mutators will be fixed, and this works with any of them
Hope this helps!