Is there any possible way to improve navmesh's terrain baking?

is there any possible way to improve navmesh’s terrain baking?
As you can see through the image there are lots of regions that are not baked well.

image

Thank you so much!

The regions that appear gray in the screenshot are not holes in the NavMesh but only places where the terrain rises above the NavMesh. That is perfectly normal. An Agent will navigate through those areas as expected. If you switch the shading mode of the Scene View to “Wireframe”, or if you hide the terrain, you’ll notice that the NavMesh is continuous.
True discontinuities in the NavMesh are always represented with segments drawn in black and they are usually surrounded by other dark gray segments that mark the polygons.