Spline landscape deformation creates a deep valley

[whatthesamuel]

I’m trying to make some roads using splines, but when I press the deform button, it creates a deep valley like this:

I just imported a heightmap I made in terresculptor, added some spline points, and pressed deform landscape to all splines. Am I doing something wrong?

[whatthesamuel]

turns out, I needed to create a new layer dedicated for splines.