Problem with grouping in a region related to lattices

So I'm grouping atoms in a lattice together, and I have other atoms
above the lattice (lattice is bottom 40% of box, other atoms are in
top 60%) when I make the lattice too small when I choose the group by
region command it seems to deform the regions, because when I choose
group wall region 1 (region 1 box 0 10 0 10 0 4), it will take the
atoms it just put down, plus a certain number of atoms that were
placed in the top, and when I use group mobile region 3 (region 3 box
0 10 0 10 4.01 10) it takes the remaining atoms not in group 1.

I'm not sure what's causing this problem, it seems to be alright so
long as the lattice size is around one.

~Nickhil Rokkam

The region command has an option to use distance units
that are either "box" or "lattice". If the lattice spacing
is 1.0, they are the same. If it isn't they can be very
different. So I suspect you are using the wrong option
for your purposes and the region extent is not what you think.