Completed lessons keep dropping out and more
I have lost days in a row several times over the past 2 weeks. Completed lessons show up over and over again as not being completed. Microphone voice recognition indicates a wrong answer very frequently even when the answer I verbalize is correct. Are these common issues and can anything be done about them?
I had a lot of issues with these exact things when I first started. Are you using the app or the web version? If you're using the app and completing lessons offline, be sure to leave DuoLingo open, (don't close the app out completely to save battery or clear out how many apps are running on your phone) until you return to an internet signal...then for me it seems to help to open DuoLingo and just hold my breath because there is always a little flicker where it goes back to what I had accomplished the day before. As for the voice recognition, I don't know but it was always worse offline and since the speaker doesn't work well offline either I've turned off speaking/listening exercises on my app and only do those on the web version.
I've had a ton of issues with numbers not being heard correctly by Duo, when I know darn well I'm saying it right and even at one point played Duo's own voice back at it and it wasn't accepted on the numbers exercises.
The other problem with skills decaying rapidly I've heard others complain about on German for English speakers. I'm not seeing it myself. But have been a little exasperated by the speed of decay in English for German speakers. I've not finished that tree yet and I don't recall it being that bad when I started German for English, but I assume it was and I just don't remember it now.
I do know the more mistakes you make, the more they will bring you back to the same lesson.
Turn off the microphone in the settings.
Make a screenshot of your not completed lessons.
Skills automatically lose strength as words decay over time. Check the wiki here: http://duolingo.wikia.com/wiki/Duolingo_Wiki
If skills gone back to 0/10, where all lessons have been completed before, then you may have received a rollout of a tree update.