In Jira Structure plugin:
I am trying to sum up the total time employees have dedicated to each project category.
To do so, I have a board with the following generators some generators you can see in the image.
I have created a formula column for each project category to sum up the totals based on the project

Where timeinprogress is a variable, and it works.
I have also selected the option "Sum over sub-items"
The problem is it is always summing 0 for groups or tasks with subtasks

What am I missing?