Neighbor list overflow

Hi everyone
I was running my input script, but I got the following error:
'' Neighbor list overflow, boost neigh_modify one ''
and after that the simulation aborted at the first step.
Can you help me please within this problem?

I am inserting 10000 small particle in a spherical region and dragging them toward the center point to make a large agglomerate using the following script:

# initialization
units cgs
newton off
boundary f f f
atom_style granular
communicate single vel yes

# region for inserting particle
region reg sphere 0.0 0.0 0.0 0.01
create_box 1 reg
neigh_modify every 1 delay 100 check yes

# physical properties of particle
fix m1 all property/global youngsModulus peratomtype 4e10
fix m2 all property/global poissonsRatio peratomtype 0.12
fix m3 all property/global coefficientRestitution peratomtypepair 1 0.5
fix m4 all property/global coefficientFriction peratomtypepair 1 0.26
fix m5 all property/global coefficientRollingFriction peratomtypepair 1 0.002
fix m6 all property/global cohesionEnergyDensity peratomtypepair 1 3e12

# particle size
fix pts all particletemplate/sphere 1 atom_type 1 density constant 1.52 radius constant 5e-4
fix pdd all particledistribution/discrete 435 1 pts 1.0

# particle insertation
fix ins all insert/pack seed 12345 distributiontemplate pdd insert_every once overlapcheck yes all_in yes region reg particles_in_region 10000 ntry_mc 1000

# contact model
pair_style gran model hertz tangential history cohesion sjkr
pair_coeff * *

# applying a constant force (almost ten-fold of particle's weight) toward the center
fix center all drag 0.0 0.0 0.0 7e-6 1e-7

# integration
fix integrate all nve/sphere

timestep 1e-6

# setting outputs
thermo_style one
thermo 1000
thermo_modify lost ignore norm no

# run 1st step to check timestep
fix ctg all check/timestep/gran 1 0.01 0.01
run 1
unfix ctg

# create dump
dump dmp all custom 1000 dump*.agg id type type x y z ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius

#
run 100000