Hi,
I need help to generate an accurate Burn-down chart for an active Sprint.
We encountered an issue where, after creating a board and a Sprint, the Burn-down chart displays incorrect data. Specifically, all issues in the Sprint show no remaining time estimates, and only recently logged work tickets appear after the Sprint is set to active.

Not all parent issues have an original time estimate. Instead, their subtask issues contain the original estimates. When viewing a parent issue with the "Include Subtasks" option, the parent issue reflects the remaining time estimate aggregated from its subtasks.
We expect that, upon Sprint activation, all parent issues will display the remaining time estimates aggregated from their subtasks' remaining time estimates.
The Board where the Sprint is located was set as follows:

What did we miss in setting the board/Sprint?
Thank you,
Kent