The pasted table at https://ask.libreoffice.org/upfiles/15811042554219983.odt
does not give any clues as far as I can tell. Your original file may still contain “residue” from the deletion/mangling of content. If you want people to take a look at that, keep an untouched (or touched as little as possible) copy. In another copy, delete everything except the offending tables. Do editing inside the tables only if you must, to remove confidential info. Editing objects will sometimes completely rebuild object structure, which may remove the evidence we are looking for.
Before that, perhaps investigate a bit yourself:
If you have enabled “version saving” for the file, there may be previous states of the document saved. See File - Versions
The file system may also contain salvageable data. Open the folder in your file manager (Windows explorer), right click the file and select Properties
, then look under the Previous versions
tab if you have that in the properties dialog.