Critical Error When I activate the plugin

My website was working but in short time ago I started to get critical error when I click the subpages and language switcher lost too. I tried with another theme too and same problem continues. when deactivate the polylang plugin, other language pages started work normally and when I visit the subpages , pages are running normally. When I activate the plugin , I am facing the “critical error” again for other languages again even if I try to visit manually.

The page I need help with: [log in to see the link]