Adding issues to an sprint
Adding an unestimated issue to an active sprint
Do you have an active sprint.
You add a new task to it that does not have a score in Story Points.
In this case, a pop-up screen will appear that will tell you that you cannot put an unestimated issue in the Sprint.
It is required to evaluate the issue by putting a certain value in the Story Points field.
After that, the task can be added to the active sprint.