Having to strengthen a section every day
Several days ago, I completed a section (Spanish, "Ir Future"), and have moved on to the subsequent sections this unlocked.
However, every day since, I'm told I need to refresh the "Ir Future" section, despite turning it gold each time. I can go through it, get nearly every question right, it turns gold, but the next day it's back to needing more work. I think it's been like this about a week.
This can't be right. Is there a known problem with this part of DuoLingo?