I was checking something in the toilet cistern. I flushed, but holding the float ball, so the cistern wouldn't be filled. With a very low level of water in the cistern, I flushed a couple of times. Then I let go of the float ball and the cistern was filled.
I didn't do or change ANYTHING.
The problem: Now, when I flush, the siphon stops the flushing at a much higher level than before, flushing much less water than before. The flushing now stops every time at the hole you see on the picture. Before, it was stopping at one of the holes on the left (that is, at a much lower level).
Again: I didn't change ANYTHING. The hole the arrow is pointing to has always been unplugged.
Was it bad that I flushed without the siphon being covered with water? How can I make the siphon go back to flushing normally (that is, almost emptying the cistern)?