I moved on to Babbel.
Quick search gave this review: The main differences between Babbel vs Duolingo are: Babbel is best for learnings looking to completely master a language, whereas Duolingo is better for sporadic learners who want to dabble. Babbel offers lessons with conversational practice and cultural immersion, whereas Duolingo offers adaptive learning lessons.
Memrise is worth a look as a Duolingo alternative. It’s similar but feels a bit more “serious”, there are some nice features like you get videos of native speakers saying phrases with a variety of accents.
I also found busuu and linq to be okay as well.