Initially, when I pressed again button, the learning red count decreased, so I changed the learn ahead limit to 5min from 0min, which resolved the problem. However, few minutes later, when I pressed again button, the learning red count as well as other counts did not change at all. I tried to change the learn ahead limit to 30-90min, relearning steps to 10m 1d from 15m 1d, and new interval to 0 from 0.20 but no change.
The primary job of the learn-ahead-limit is allowing Anki to make a Learn/Relearn card available sooner when you have no other cards to study – Preferences - Anki Manual. Whether that changes the red counter or not is somewhat beside the point. The key indicator of whether it is working is whether the card is offered to you again before the end of your study session.
However, setting a learn-ahead-limit that is less than your learning steps – to 5m – is probably the opposite of what you want. That will mean Anki will show you cards up to 5 minutes before they are due, when there are no other cards to study for the day. (If you set it to 0m, Anki will not show any cards early.) If your short-interval steps are 10m and 15m, you should set it to at least 15m.
I don’t think the learn-ahead-limit is intended to work with cards that are already set to be due on another day. If you have cards on a 1d step, you’ve already decided not to study them again today, and Anki will leave them set where they are.
The New Interval is entirely unrelated to the learn-ahead-limit. See: Deck Options - Anki Manual .
But the point of again button is to do it again that day and I’ve tried to set my intervals shorter but did not resolve the problem. I attached a screenshot below.
Previously, I did not have this issue despite not changing the intervals or limits.
What about your daily limits? Particularly the Maximum reviews/day limit.
When I press again, hard, or good, the counts do not change but with easy button the red learning count do decrease. However, for some decks, I have no issue at all.
The point of Again is only to do it again the same day if that’s how you have your steps set.
I think there might be another issue overlapping here. Since you previously had a 1d+ learning step, I suspect that you’ve had a lot of cards in learning when you’ve been making these changes. That can cause those cards to skip or repeat learning steps, so you might not be seeing an accurate application of the setting. After you study those cards another time or 2, they will get on the right track.
If you have this issue with cards that have been newly introduced with no changes to the learning steps, we should look at what is happening.
This is a good reminder to check and make sure that you’re looking at the Deck Options for the correct deck – the deck the cards are actually in, not the parent deck you click to study.