Duration fields on list view do not display seconds if the duration goes above a minute and further. This issue is a result of PRB792621.
The permanent fix for this issue is to add the following sys_property (PFA):
Type: true | false
- All, new instances will come with this property OOB, upgraded instances will need to create this property
This property will come OOB with new instances and default to false. Please create this property and set the value to 'true' for the seconds to display if the property does not exist in your instance.