If you host your VPS with Xen environment, you will found out your local time will follow the dom0(host) time.
To get this fixed, you may follow here,
1. Edit the value in /proc/sys/xen/independent_wallclock,
echo 1 > /proc/sys/xen/independent_wallclock
2. The make sure the setting run on boot, edit the file /etc/sysctl.conf, enter the following line to new line.
xen.independent_wallclock = 1
3. Lastly, log into WHM, select Server Configuration, select Server time and Sync it with Time server.