Date notation/format working every language, except one

Hi All!

I have a strange case and I can not find the reason (or solution).
I have a multi language/locale website. When I change the locale, the notation of the date changes with it. As stated here:

So In French, I see a date like this: 01/06/2020 and when I change to German, it is this: 01.06.20 and in Dutch it is 01-06-2020 . Perfect!

But when I upload the project to my webserver, I encounter a problem: All languages behave as expected, except for one (Dutch). So I think there might be something wrong with the server? But I can not figure out what (what to look for, what to Google).

So my question is: Does anybody have an idea? Is it my server? Is it something else?
Help is much appriciated (have been struggeling for 3 days now).


Could it be a case change in some name? Possibly your local server and production server handle miss-matched case differently.

Check the version of ICU that PHP is built with.