Sprites with shadow caster behaviour act differently under different angles of shadow caster

Recently I've been experimenting with shadow light in my game Devoid. It should work like it normally does, but some sprites don't cast shadows depending on the position of the shadow light.

In the below image, a sprite on the right of the screen does not cast a shadow

In the next image, the same sprite casts a shadow, but in its place another sprite refuses to do so:

For each of the shadow caster sprites, i did modify the collision box so that it reveals some of the sprite, for the sake of the game not just having black walls. How do i fix the sprites not casting shadows, or are there alternatives to the effect that I'm aiming for?

Shadow lights can only handle shadow casters which have convex collision polygon shapes. So the effect will break on shadow casters having concave polygon shapes. Make sure that's not the case and that there aren't multiple polygons on the exact same spot.