Clips have been duplicated in Productions

When you are working on a Production in which there is one project with imported media, another project with media sync via multi-camera clips, and other projects with timelines. Sometimes in these editing projects, when you open them, the multicam clips or the video clips are imported directly, and if you reassociate the source clips, they disappear from the project because they connect with the real source, which in fact was already there when you created the editing.
The error therefore seems to be that the connection with the production project, which is the origin of the clips inserted in a timeline, is lost, but it is not known why this happens. It's obviously a Premiere bug, but no idea why it happens.

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