Progress suddenly reset for some steps

Hi :),
I was learning " Responsive Web Design" and I’m already at “Learn Accessibility by Building a Quiz”.

Today I logged in (as usual) and was surprised that “Learn HTML by Building a Cat Photo App”, the very first part of the course, has lost some of its progress.

It’s now at 97%. I was surprised. It also not plausable that I leave certain steps just for fun :).

These “open” steps are also missing from the timeline as if I’ve never done these.
Because I’m not donating right now, I don’t expect nothing, but I thought I inform you there might be something wrong in your web application.

Also when I click on step 71 (the last step), it looks completely wrong.

Have a nice day.

Regards,
Andreas

a new version of the beginning of cat photo app has been released, there are a few completely new steps, which you have never completed, so they appear like that. You can ignore that and continue forward from where you are