Particles' data stops reporting near bottom boundary in Periodic Boundary Condition setup

Hi Everyone,

Could someone please help me with this challenge.
I am simulating the settling of particles in a periodic domain but notices that .liggghts files stops reporting any data once the particles gets to the bottom of the container. I am using an lbm-dem coupled code with liggghts version 3.1.0. The liggghts main input file is pasted below:

echo both
log ${dmp_dir}/log.liggghts

units si
atom_style ellipsoid # granular #
atom_modify map array

communicate single vel yes

boundary p p p
newton off

processors * * *
atom_modify map array sort 0 2.0

region box block 0. 0.02 0. 0.02 0. 0.05 units box
create_box 1 box

variable skin equal 0.001
neighbor ${skin} bin
neigh_modify delay 0 every 1 check yes

fix m1 all property/global youngsModulus peratomtype 1e6
fix m2 all property/global poissonsRatio peratomtype 0.4
fix m3 all property/global coefficientRestitution peratomtypepair 1 0.5
fix m4 all property/global coefficientFriction peratomtypepair 1 0.45
fix m5 all property/global coefficientRollingFriction peratomtypepair 1 0.020

# lb coupling fix
fix lbcoupling all couple/lb/onetoone

#pair_style gran model hertz tangential history rolling_friction cdt
#pair_coeff * *

fix 1 all nve/asphere

variable rho_solid equal 1164

variable g_red equal 9.81*(${rho_solid}-${rho_fluid})/${rho_solid}
fix grav all gravity ${g_red} vector 0 0 -1

# fix zwalls1 all wall/ees zlo EDGE 1e-15 3e-5 6.735e-5

#lattice sc 1
variable d_part equal 0.002
variable mass equal 4.88E-06
variable dx_part equal 0.0026207
variable dy_part equal 0.0017472
variable dz_part equal 0.0017472

#variable z0 equal 0.07+${d_part}/2.00
variable z0 equal 0.041+${d_part}/2.00
variable z1 equal 0.036+${d_part}/2.00

create_atoms 1 single 0.01 0.01 ${z0}
create_atoms 1 single 0.0099 0.01 ${z1}

# Group particles by type
group red_particle id 1
group green_particle id 2

# Assign custom properties for visualization
variable color atom "type"

set atom 1 mass ${mass} shape ${dx_part} ${dy_part} ${dz_part} quat 0 0 1 90
set atom 2 mass ${mass} shape ${dx_part} ${dy_part} ${dz_part} quat 0 0 1 90
#diameter ${d_part} #density ${rho_solid}

run 1

Thanks for your anticipated assistance