Missing/Replaced Unity default mesh Assets?

Hello! I've been playing around, trying to create a custom mesh from code, and called "GetComponent ().sharedMesh.Clear ();" on a standard asset cube.

It seems all the standard vetices and triangles of the Unity3D cube mesh has been replaced with a clear mesh.

So, Is there a simple way to Reinstall the Unity Default Resources, or do I have to Export my assets to a new project?

Here's the whole script, by the way:

         mesh.vertices = points;
 
         mesh.triangles = triangles;
 
         GetComponent<MeshCollider> ().sharedMesh.Clear ();
 
         GetComponent<MeshCollider> ().sharedMesh = mesh;
         //detectionCollider.sharedMesh = mesh;