Configuration problem with Charts

Hi All,

I’m having problems while trying to enabling Charts.
I went through the following guide to enable it:

But I’m still getting the “Graphical charts are not available” message on
the Charts page.

The GD dependencies are OK.

I’m using RT 4.2.12 on CentOS Linux release 7.2.1511

What did I missed?
Can anyone help in this issue?