Segmentation fault while running a simulation

lmp_ubuntu:18362 terminated with signal 11 at PC=55f3b7ddfb32 SP=7fff1a9fa320. Backtrace:

the above message appeared after a while of running the simulation, even though it prints the simulation results halfway. It is not able to complete the simulation. Please what can I do to fix this

Unfortunately, there is no usable information here to be able to tell what went wrong, thus it is impossible to give advice. What does “after a while” mean?

It would be helpful, if you would recompile your executable with debug info included (“-g” flag added to LINKFLAGS and CCFLAGS, followed by “make clean-ubuntu; make ubuntu”) and then run within a debugger to produce a stack trace as shown here: 11.4. Debugging crashes — LAMMPS documentation

Since you have partial output, does it look correct? Are energies reasonable? Are there any indications or warnings? Do you have a trajectory? If yes, have you visualized it and does it look reasonable? Or is there anything unusual, especially toward the end?

Can you try and set up a (much) smaller system with fewer atoms that reproduces the same kind of crash, so that it will be easier to debug?