I am using piwik for a just mobile app. So there is no web server. I am using iOS sdk. It was working until one month ago but yesterday I saw below error in Matomo website when I wanted to check the graphs.
Oops… there was a problem during the request. Maybe the server had a temporary issue, or maybe you requested a report with too much data. Please try again. If this error occurs repeatedly please contact your Matomo administrator for assistance
When I change the time to one year ago, this error would disapear for some of the fields.
Also, I should mention that I did not update my piwik from 3.3.0 to newer versions. Could it be because of this?