The file is malformed. This message usually tells where is the issue. Reexporting with calibre usually helps
This error pops out when kavita scanner doesn't detect any files where it had already detected files.
This scan was aborted to avoid wiping user progress and series data if there is a mounting error.
The internal epub metadata is not pointing to the right files.
Try exporting the file with calibre or any tool that manages to fix the file metadata.