Thanks Dennis but this procedure did help to solve the issue.
BTW please note that some panels has data and some not.
If I edit the panel that does not show data and select generate query, click refresh, I can see suddenly the data in this view, but when I come back to the dashboard view, again… the widget it empty black.
Click on “Datasource” Select the datasource again, apply and save, I wait for your feedback.
even if it is already in the correct datasource, put it again