When performing an action such as subtracting a feature or buffer or splitting a feature you notice that the subtract or split is not being performed. This is most commonly because there is a geometry issue somewhere in the plan which is causing this functionality to fail.
Land App has a Geometry Fixer tool which will try to resolve any issues. To access this click on the three vertical dots next to your plan name and select Toolbox.
Select Geometry Fixer
Select Run
Select Back to map
Please note you may need to refresh your map to be able to see the plans created.
You will receive an email confirming your data has been validated and, in your map, you will see additional plans that show what has failed, what is valid, your issue locations and invalid parts.
The valid plan will be a fixed version of you original plan which you can then use. The other plans, for reference, will show you where the issue were in your original one.