Why does Anki have index cards in the wrong sub-pile?


I’ve only recently started using Anki. I have created a main pile with various sub-piles. However, when I call up the first sub-pile to learn, for example, all the index cards I added or saved in the first sub-pile do not appear, as I suspected, but many cards from other piles, and I don’t understand that.

I also don’t know whether that has anything to do with the fact that I exported the batches from another computer and imported them on my current computer in order to be able to continue with the creation of the index cards.

Does anyone know how I can get it back so that when learning only the cards appear in the respective sub-stacks that were actually added or saved there?

It would be great if someone could help me here.

A screenshot of your deck structure and a specific example would help to understand what your problem might be.