Sprint Velocity Report not calculating sub-tasks time

[vance.duke]

Background: Our team was using Jira 8.1 and has recently updated to 8.14 and are using the data center version. We have been doing Sprints for quite a while and we use the Time Estimates and Remaining time for planning and burn down.  Late in 2020, we started moving to sub-tasks, and applying our time estimates and remaining estimates to the sub-tasks.

Early in 2020, we had a great velocity report and we could see that we were doing 5-6 weeks of work per sprint.  We could see the velocity, and at the time, I was calculating the average. Late in 2020, we started moving to using sub-tasks.

Since January 2021, we have been working exclusively with sub-tasks for activities, and there are only a small number of stories level items that have a time estimate.

However, when looking at the past 3-4 sprints in 2021, the velocity is around 1 week. The commitment is about 1 week, and completed is about the same. When I look at the Burndown report, I can see that the commitment was anywhere from 4-6 weeks, and completion is also 4-5 weeks.  It seems like the Velocity report is missing something.  I had hoped that with the update to v8.14 this might have been resolved already.

Does anyone have any insight or suggestions on what might be occurring?

Thanks