one of my lessons doesn't update when I complete it
I'm using Duo to help learn French. It's working well except that lesson set 'People 3' doesn't update the 'completed' tally once I've finished a lesson. It's currently stuck on level 3 and is showing 0/15 completed even though I've probably run the lesson that number of times already. This isn't happening with any of the other lessons.
Some people solved this issue by testing out of that skill (tap the key icon)
Thanks but I can't see a key icon anywhere. My phone is android - I know that Duolingo works differently on different phone operating systems so perhaps this is a feature available on an i-phone or windows phone but not android?