In Piwik there is the possibility for users to delete old log data:
When a user has setup Piwik to delete old log data, it may happen during normal use of Piwik, that a user requests a report for a very long date range.
Not sure the best way to solve this...
You have requested a report going as far back as YYYY-MM-DD. Unfortunately, your Piwik is configured to delete any log data older than N days. The earliest date range you can request is the following: &date=YYYY-MM-DD,YYYY-MM-DD(eg. see
Follows up https://github.com/piwik/piwik/issues/10261#issuecomment-229373850