New lessons don't get saved
I'm doing new lessons (tried two different ones), but when I finish them with hearts still left and the lesson shows as if it is completed the progress doesn't get saved. When I get back to the subject page (e.g. Objects or Adjectives) the lesson still shows up as new and I can't progress to the next one.
I have made no changes to my environment except for using a different internet connection in a different country. What could be wrong?
Edit: It only seems to happen in those two subjects it seems. Finishing a lessons successfully in the Places lesson works fine.