with the latest Matomo version 3.13.0, an E-Mail report (PDF) segmented by URL (URL starts with) contains incorrect data: Also data from URLs not starting with the given URL are included.
This is visible in the Diagram "Aktionen - Kernmetriken" (Actions - Main Metrics?) in the page count (which is too high) and the listing of page titles (which includes pages not starting with the specified URL).
There is a workaround to restore the old behaviour see https://github.com/matomo-org/matomo/issues/15137#issuecomment-552571872
We understand this may be frustrating that this behaviour changed but there is no way for us to make the behaviour right for everyone.
Sorry for the duplicate, I did not find the related issues.