Issue Downloading MMPBSA Program on Gromacs

GROMACS version: 2020

Hi,

I am trying to download the MMPBSA energy calculation program but although the terminal shows that it is downloaded, the command line does not work.

I activate MMPBSA by entering:
conda activate gmxMMPBSA

However, when I try to eneter the following command line:
gmx_MMPBSA -O -i mmpbsa.in -cs md_0_10.tpr -ci index.ndx -cg 20 21 -ct md_0_10_fit.xtc -cp topol.top

I receive this:
gmx_MMPBSA: command not found

Here is the entire series of what I input
(base) bioinformatics@BioResearch:~$ conda activate gmxMMPBSA

(gmxMMPBSA) bioinformatics@BioResearch:~$ gmx_MMPBSA -O -i mmpbsa.in -cs md_0_10.tpr -ci index.ndx -cg 20 21 -ct md_0_10_fit.xtc -cp topol.top
gmx_MMPBSA: command not found

Is there something I did not do in the installation that is causing this?

I appreciate any help in advance.