lammps diffusion

When looking at the mean squared displacement (MSD) of my monomer systerm using post-processing code, I found what seems to be an interesting error. There seems to be some maximum amount the particles can displace in the direction of the electric field before resetting to zero…Is there a maximum number of boxes it can diffuse before a forced restart?
Attached is an example input script, data file, and MSD plot. The dump files are unfortunately too large to attach.

PEAAefield5V.in (1.48 KB)

peaalidat (709 KB)

msdplot.pdf (94.8 KB)

If your particles wrapped around a periodic box, then your
post-processing code needs to be clever enough to account
for that. You can dump image flags with your dump file
or dump unwrapped coords to help with that. Or you can
use the compute msd command in LAMMPS (which accounts
for this) and compare your answers to that.

Steve