Box Colliders not working correctly

So Im trying to build a basic 2d jumping game using the 3d work(easier way for me to code) I have a long rectangle cube as the floor where the “jumper” rests and moves on. When nothing else it touching said cube, the collider works fine, but when something is connected to it, like a cube turned 45 Degrees to simulate a triangle, my players digs itself all the way into the floor. Please help.

Edit: I can’t continue with the project because this is causing my jump to not work properly

try taking off the rigidbody?
its too expensive for a ground, and might be conflicting with the rigidbody that I assume is on your player

Why?

In any case I recommend looking into friction etc of the PhysicsMaterial

That somewhat helps. The jump is too small rn, ill just add some more force to it.

ive added force and its works. Thank you!

i reduced all drag i could

Why is it too expensive? I thought rigidbody calls the physics engine, and if every ground had a rigidbody, that would be a lot of physics calculations being called over and over for objects that usually don’t need physics, and appears true in this case from the screenshot.
also, cant friction be set up on the player controller?