The time worked field is not updating when deleting or updating time worked records (task_time_worked records) from the Time Worked related list on incident records.
There is a system property named 'com.snc.time_worked.update_task_timer' which needs to be enabled.
1. Enable the property named 'com.snc.time_worked.update_task_timer' (by setting to true) which will activate the business rule named 'Update task time'. This business rule will recalculate the Time Worked field on an incident when users update task_time_worked records.
2. If users want the Time Worked field to be recalculated when users delete task_time_worked records, users will need to update the business rule to run on deletions (default is just inserts and updates).