Halløj allesammen!

Has anybody else been having trouble strengthen their skills by using the "Strengthen skills" function from the home screen? Thankfully, the early bug where I was consistently being asked to translate "armbåndsuret" into English has gone, but I've encountered another issue.

Maybe this is something that happens across all languages on Duolingo, but I find myself consistently unable to actually strengthen skills in any category even when I achieve scores of 18-20.

Is this the way the activity is supposed to work?

Thanks for any help.