Progress isn't saved

I hadn’t been on fCC for some time but wanted to get back into it so I logged in with my normal credentials and noticed that under the curriculum, nothing is checked, indicating that I have no progress. Not too big a deal as doing it again is a bit of a refresher anyway.
However, my curriculum still doesn’t show completed challenges as “checked”. Does anyone know why this is? I am just doing the basic HTML curriculum. This I can double check as on one of my computers, after doing a few challenges, going to the curriculum shows a few checked challenges, but then logging in on another computer shows zero progress. I don’t expect this to be a cookie issue as the progress should be credentials based.
Thanks

I’m having the same problem, challenges have been correctly marked for a while, but suddenly, from a certain point, they stopped being saved

Same here. I’ve been through a massive chunk of the previous curriculum before the switch to the new one. Now, none of my recent progress was reflected in my profile, and the checklist still insists that I’m not yet done with those items even if I already finished them.

Finally found out what I’m doing wrong, at least, to display check marks on the curriculum page.

After completing a challenge, you have to click on “Submit and go to next challenge” to mark it as complete. It still won’t show up in the calendar, but it would be displayed on the timeline and it would be marked on the curriculum page.