This is probably related to LingQ deleting most of the oldest courses at the end of last year to free up storage space. The files were permanently deleted by a developer and can’t be restored - I asked. A clerical error really, there is no one to blame. But it’s certainly unfortunate this had to happen, with this they wiped out some of the most popular and helpful courses ever. All the older libraries were affected. Here is a related thread concerning the German library: Irene's German lessons disappeared from library. Why?
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