Energy increase during minimization with indenters

Dear all,

I am running minimization of a MgO nanoparticle which is strained by using two indenters. I am using lammps 1Feb14.
I got the issue that during the minimization the energy might increase when using fire or quickmin minimizers. The energy typically first decreases, then after going through a minimum it can increase by more than one eV.
I do not get this issue when using conjugate gradient but I need to use fire of quickmin since I want to run NEB calculations.

I apparently do not get this issue without the indenter.

Are the indenters and the fire minimizer incompatible?
Am I doing something wrong?
I put my input script at the end of this email.

Thank you in advance for your help,

Emiile Maras

First, please use the current version of LAMMPS.

If the problem persists, then post again.