This is because you have added story points values to stories after the sprint has started or you have added new stories to the sprint mid-way. Sprint report will only take into account the story points for the initially committed scope.
A feature request GHS-8776 is already logged to show the actual completed scope rather than the initial committted scope.
A workaround can be to use the burndown chart instead.
Also have a look at the link below and the answers discussion on this topic.
Atlassian ranks project attributes as the third most important factor impacting performance in the category of data. It’s not surprising, since project attributes are precisely the rules used to ma...
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