Part of widgets disappeared from sidebar

Hi,

Yesterday I noticed that on my site: https://www.imperiumromanum.edu.pl/
bigger part of my widgets on sidebar suddenly disappeared – withou any reason. I haven’t done any crucial amendments. Only one week ago I updatek WordPress and several plugins. But there were no problems.

On right side of website we can see only Custom Google Search and plugin Recent Posts Extended. Disapperaed sections: POLECANE, CIEKAWOSTKI, ODKRYCIA, KONTAKT, REKLAMA.

Can you help me find the reason of such situation?

I can add that in CMS everything looks fine, apart the fact that mentioned widgets are not present.

Please help me with the issue.

Best regards,
Cosiek