Brush will not move onto image

Hey,

from time to time I have the problem that the brush will not move onto the image. It literally stops at the corner of the image. I can surround the image with the brush, no problem. But as soon as I want to move it over the image itself it stops moving.

Using other tools like magic or AI brush or the eraser brushes work fine.

Unfortunately, I can't detect a pattern to reproduce it. Also getting rid of it is not, as far as I discovered, a way of specific steps. I switch the images, open other sessions, stop and start etc. End then, eventually, the brush is back working normal.

Any ideas?