NR , thank you for contacting us.
I have checked the course, the contents are still available and the course is still active.
Regarding chapter 1 and activity "Let's learning", please upload a file in order to complete the activity. If you are referring to issues in other activities or chapters, please send us an email at email@example.com with the detail on which chapters that you are seeing this issue so we could investigate it further.
Hope this helps and please let us know if you have any further questions.