[Bug] Large share of visits have an unknown region

[9joshua]

What happened?

35% of a Cloud customer's traffic comes from an 'unknown' region. IP anonymisation occurs after enriching visit data.

I do not have a full IP address to test against Maxmind, but using an anonymised IP from their visits log does return a region using Maxmind's demo...

This is similar to #20527 which has been closed.

What should happen?

I would expect the % of unknown regions to be far less than 35%

How can this be reproduced?

View the Region report in Visitors -> Location for a French or German based site. (Probably other countries as well)

Matomo version

5.1.0

PHP version

8.2

Server operating system

Linux

What browsers are you seeing the problem on?

No response

Computer operating system

No response

Relevant log output

No response

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• Check that there isn't already an issue that reports the same bug to avoid creating duplicates.
• The provided steps to reproduce is a minimal reproducible of the Bug.