[Landmass Blueprint Brush] How to get the paint layer to replace the layer below it?

Whenever I use the Landmass Brush to create Landmasses and then use paint layers to paint them, it does not replace the painted layer below them, it blends with it.
For Example, I have a base layer with Red material painted on it.
If I create a second layer and then use the landmass brush to create and paint a landmass with green color, it turn out to be yellowish.
But If I use normal brush to paint, then it replaces the red with green.
I haven’t found any setting in the landmass brush regarding the weight it uses to paint.
So, is there any way to do this?