Time span always 4 times as long as selected

Hi,

we were having problems with the last visitor graph not loading. After update to 3.5.1, deleting and regenerating the archive the widget now displays, but never shows the timespan as selected.

If one day is selected it shows 4 days, if one month -> 4 month and for one year it shows 4 years’ data. Thats probably the reason, why the widgettimed out in older matomo versions.

How can this be fixed?

Thanks for any help!
Sincerely