1- Go to Administration > Substatus > Rules and scroll down to the “System Clock Pausing” section.
2- Select a Substatus that automatically pauses the system clock (i.e. all Total Time Open, Escalation and SLA calculations) on issues.
3- Click Save.
The message “Substatus will now pause the system clock” will display and the new Rule will appear in the Clock Pausing Substatus List when the save is complete.