I am using isometric camera settings. In Probuilder, I create an object and delete a edge from it; after that, the adjacent edge and side edges become invisible, and if viewed from a different angle, they are visible. How to solve this problem?
That’s normal. It is because it’s a plain 1 side is visible the other isn’t.
You can however make another one and turn it for 180°
Try using Probuilders Flip Face Normals tool with the faces selected that are invisible to the camera
If all the faces are wrong then you can use Flip Normals - Object
https://docs.unity.cn/Packages/com.unity.probuilder@5.0/manual/Face_FlipNormals.html
https://docs.unity.cn/Packages/com.unity.probuilder@5.0/manual/Object_FlipNormals.html