Getting permission denied error while access Unix Filesystems in JupyterHub

We are have installed jupyterhub (2.3.1) with Python 3.6v on redhat linux 7 platform.
The jupyterhub service is running with non-root user, with application account as we used the same application account to install Python and Jupyter Hub.
Users are getting permission denied error while access their Unix File Systems from Jupyter Hub. They are able to access the same from putty.
Appreciate advise here for fixing the issue. Jupyter module versions installed:
jupyter-client (7.1.2)
jupyter-console (5.2.0)
jupyter-core (4.9.2)
jupyter-telemetry (0.1.0)
jupyterhub (2.3.1)
jupyterlab (0.27.0)
jupyterlab-launcher (0.4.0)
jupyterlab-pygments (0.1.2)

This is a duplicate of Permission denied error to unix path in JupyterHub

Yes @manics . Provided more details like versions etc in this post. Can you please advise me if anything wrong with the config? Let me know if I need to provide more information.