Firstly, I am sorry if I caused a misunderstanding, but I am not a troll, and neither am I in a certain position of responsibility - I'm just a regular OSM user like you, trying to improve the map little by little :-) I got notified about your changeset because I use a personal rss-feed for an area which includes the park where the drinking fountain can be found (Mexikopark).

I don't use the mapsme application, but I use Organic Maps, which is a fork of mapsme - and when I checked it myself, I realized that the "old" fountain, which already existed in the OSM database before, also did not show up on my map. I understand why you mapped the fountain there. There are, however, two objects of the same type now existing next to each other in the database - see: https://www.openstreetmap.org/#map=19/48.22425/16.40427 (zoom in to the closest level possible). I have no idea why the apps are not showing the already mapped fountain.

If it's true that there are indeed two fountains so close to each other in reality, then your addition is totally fine. If not, I believe that the newly created fountain should be removed from the database, to avoid duplicate items.

Best regards,
Schnitzl