"last month I did upgraded to the last version of mojo, but my client did not like new Tiny, so I did downgraded it back to 188.8.131.52.. can this be the problem ?.."
yes of course that caused the problem, you cannot downgrade because you already upgraded and that made changes to the database that will not be reversed.
To fix the problem upgrade again to the latest version of mojoPortal. If you don't like the new TinyMCE after that then ask a new question about it. It is possible to change back to an older version of TinyMCE without downgrading mojoPortal.