Not getting correct density

Hello all

I am using LAMMPS version 31 March, 2017. I am trying to simulate the Gay Berne particles (4.4, 20, 1,1 ) using fix npt/asphere for pressures P=1 and P=2 to reproduce the published results. But I am not getting the desired data. I am getting the density values lower than the published values by same amount (0.06) for isotropic liquid for different temperatures for both P=1 and P=2. What can be the reason behind this? Where am I getting wrong? Please help me out of this.The input script and plot are attached below.

GB_P_1.0.in (1.77 KB)

isotropic.pdf (56 KB)