Only just started using Fluent since the German launch and I'm getting the same bug.

I'll do practice, it shows full green bars and that it'll start showing the word less often, but it will then show me the exact same word right after. I've done "carpet" and "patio" at least 50 times now correctly with nothing changing.

According to my profile, I only have 2 bars on all those words, with one word in the "At Home" category never showing.

It seems almost definitely like a bug at this point preventing me from continuing making any progress.