I got to 14kyu by playing and reviewing games, plus some some tsumego and pro game memorisation.
Then I decided to buy a couple of books: “Tesuji” and “Attack and Defense” - both from the Elementary Go Series. I also took a break for about a month.
Since then my rank has started to drop. Perhaps I have started to forget the basics? I don’t really know.
Any advice would be appreciated. Do I just keep playing and hope that I improve again?