Puzzles Dashboard Internal server error on site https://lichess.org/training/opening

It says Internal server error, when visiting in German :
(Aufgaben -> Aufgaben Übersicht -> Nach Eröffnung)

I think in english it is called
(Puzzles -> Puzzles Dashborad -> under something with "openings")

Got the Same bug

Hello,

We're aware of the issue, it should be fixed tomorrow morning EU time.