Went to do my excercises for the day and all my decks are broken, they show "due today" and an amount of cards but when you click study they are all zeros.
The workaround for this is to go into edit and see which cards are reading zero open a second tab to the lesson itself verify the zero progress words should be in the lesson and then re-add them to the deck at which point they will revert back to 100% (unless they weren't 100% in the first place) then launch the deck and it should display that you have no cards for that day.
Needless to say I did not go thru my hundreds of decks to fix every one of them, the onus for this is on you Japanesepod101 to once and for all hire a programmer who does not consistently break your flashcards, my patience is growing thin.