404 not found for hints and curriculum after login

When I log in and click to go to the curriculum I get a 404 error. When I can finally access a lesson if I click on the get a hint button I get a 404. This is very annoying because I am locked at the same lesson because the code I want to make is not validated and I can not get hints to correct it. When I search for the hint if i click on the result then again I get a not found.
I don’t think it is from me because I tried with other browsers and other computers.
Thanks for the great website you provide here!
Hope you’ll find why I get this issue.