It would help to see the Card Info for the card this is happening with, but here’s a partial list of possibilities –
- Changing the re/learning steps while a card is in Re/Learn can cause skipped or repeated learning steps.
- These might not be the right Deck Options for the deck/subdeck the card is actually in.
- Intervals that cross the day boundary are converted to 1d.
- You’re studying in a Filtered/Custom Study deck with reschedule-based-on disabled.
[I would be remiss if I didn’t suggest you leave all of this tweaking behind and enable FSRS. It’s simply a better scheduling algorithm.]