To enable the stats you need root login details.Once you logged into your WHM as root user follow the steps.

Look in “Server Configuration”.
Choose “Statistics Software Configuration”.
Scroll down to “Statistics Processing Configuration Summary”.
Click on “Configure Statistic Process Time Schedule”.
Tick the boxes to denote the times during which stats should not be run.
Click “Save”, and exit.

As well as you also need to follows the steps in Tweak settings

Open whm and check “Server Configuration” listing.
Click on “Tweak Settings”.
Scroll down an check “stats Programs”; tick the boxes.

Scroll down and check bottom site; click “Save”, and exit.