There are 2 ways to activate Auto Tracking
1) In the live page, there is 'Auto tracking' button
Just click 'on' and then auto tracking will work
1) In the setup page
Go to 'PTZ' -> "Preset setup'
2) Add preset -> Make it sure that camera has preset
3) Choose 'auto tracking' from 'After action'
4) In the live view, execute Preset that has auto tracking
※ When auto tracking is enabled, 'T' is displayed at the up right corner