ERROR des\\check_cell_movement.f:178

Hi everyone. In the case particles are detected in a ghost cell. I search in forum. Researchers think there are four reasons:
1.mesh or geometry
2.DES grid search parameters
3.max steps between neighbour search is too small

Unfortunately, I tried all of these and failed. My geometry is simple 2d. I don’t set DES grid search parameters. I once decreased the max steps between neighbour search from 25 to 5 and still failed.
In the following case, I increase the kn from 1000 to 3000 but do not work. (4.6 MB) (30.6 MB)

Sincerely hope someone can help me.
Best regards!