Flattened Custom Report (2 dimensions) is missing rows where only 1 dimension is reported

I think I saw an article or post a while ago about this issue, but can’t find it so I figured I’d post here and see if anyone can point me in the right direction or advise me on how to work around this. (Also, bug or intended behavior?)

I have a custom report that reports the visits for 2 custom dimensions: country code and region code (different from the Matomo location). Usually the region code is not reported and we only get a country code. So in my example today, we have 605 visits that just reported “Country: US” and 2 visits that reported “Country: US and Region: FM.”

When I request a hierarchical report (via both Matomo UI & API), all of these visits show up correctly, US says 607 total and US - FM says 2:

But when I request a flattened report (via both Matomo UI & API), the “Country: US (only)” row completely disappears, and only the “US - FM” row is counted:

So it looks as if “DE” is the most reported country code, even though it only has 88 visits compared to the 607 for “US.”

Intended behavior or bug? Any way to work around it other than just requesting the hierarchical report instead? Perhaps a config value, API parameter, etc.?

Hi there,

Can you confirm you are using the latest version of the plugin and Matomo? If not please upgrade and try again. Get back to us if the issue continues.


Hi Jason,

Yes, we just updated to the latest version about a week ago, double checked just now:


(We are using the whitelisting plugin, which was why I blacked out our site name.)

Worth noting I have only seen this in Custom Reports so far, I don’t think I’ve had this problem with other modules/plugins I’m using (like Actions, Events, VisitsSummary, etc.)


Ack, sorry, just realized I never checked the plugin, that does need an update. I’ll bet that’ll fix it. I’ll let you know if it doesn’t though. Thanks for your help!

Never mind, I just updated to 3.1.20 and I’m still experiencing this bug. Again, both in the API and the Matomo UI, and only with flattened reports. Let me know next steps.


Hi Mikky,

We’re still investigating and have added this bug in our backlog. So far we haven’t scheduled a fix but hopefully we will in the next few weeks. Thanks for your patience!

Hi Matthieu,

Thanks so much for the update! We have a workaround for now but it’s a bit clunky, so we’re excited to see a fix at some point.

Thanks again!