Why did the Sprite Share Controller stop working?

Question

C++ / C#

To create 2d levels I used a gray box (Sprite controller + polygon collider).

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In general, it is convenient to build levels for tests in this way. At some point, with all the ready-made boxes on the stage (only on one stage, everything else is in order) some kind of devilry began to happen) When you try to edit a piece of the level, the position of the point is reset and flies away to no one knows where.

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It seems that the point resets its position to X0 Y0. With each next click on the line, the next point also goes to 0 0 coordinates. In short, after a few clicks, all points go to X0 Y0

. If, however, a new controller prebuff that I used is pulled onto this scene, it works without any problems

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I do not want to rebuild the level of course, but I want to understand what the problem is. Since in the future I may encounter the same. Maybe you know what to do?