In the editing canvas with Nano Banana, the brush stroke is not working correctly; in fact, it doesn't work at all. What could be the reason?

In the Nano Banana editing canvas, the brush stroke doesn't work correctly; in fact, it doesn't work at all. When I make a stroke, it generates multiple strokes outside the range where the original stroke was made. I can't embed notes or regions, and when I use the fill option, the brush activates correctly, but I can't type the prompt. I return to the prompt, and the brush doesn't appear where I want to edit. I don't know if this only happens with Nano Banana or if it happens with all of them, but for now, it's happening to me. I haven't had any problems with the generation of the brushes.