lost versions

it seems that about 18 days of editing have been lost in all of my writer documents - for example the last available version for document 'osnovni zaplet' is 11.6 - 18 days ago, and i had been editing almost every day during the last 18 days.
i don't remember the version numbers, but for sure, each day that i logged in, there were the correct versions and (more important) the correct text, unil today. (i didn't log in during this weekend.)

now, it seems that the system has reverted all the documents to some day mid june (18 days ago).
please help, i have lost important data.

kindr regards,
mirjana