What you post looks like four stretched cubes… the leftmost dark one is simply placed inside the other. Move it out.
If that’s not your question then you need to provide a lot more information:
How to report your problem productively in the Unity3D forums:
This is the bare minimum of information to report:
- what you want
- what you tried
- what you expected to happen
- what actually happened, especially any errors you see
- links to documentation you used to cross-check your work (CRITICAL!!!)
If you post a code snippet, ALWAYS USE CODE TAGS:
How to use code tags: Using code tags properly
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