maybe you remember that I had the same problem. I tell you my findings (and a workaround), it might help you (and others):
in Firefox the map is loading (slow but it loads in the end)
I saw that a lot of people of Berlin (Germany) where located in one place (there are several markers on top of each other)
there were different people on top each time I reloaded (the others where not available)
I changed in Firefox to a more specific location: it did change the text inside my profile but that did not change the map
I wrote you and you said that you changed my marker again and you can see me, I couldn’t (and gave up)
Today I tried something new:
now I checked with the developer tools: no issue there but also no entry with my name
I opened the map page inside the Chrome browser: the page redirects to the home page and the map can’t be accessed
but: I changed my profile there in Chrome, and there – inside the Chrome browser – is a drop-down connected to this map address field (that drop-down was not present inside Firefox on that page)
so I changed my address there with help of the drop-down and saved, and after that the new position was visible on the map!
So I got now my unique position inside Berlin.
I assume the address input seems to need the drop-down (that works in Chrome) and instantly saves the coordinates. As in Firefox that drop-down doesn’t work – one might think one did set something with the address, but that is not enough, you do not set your coordinates inside Firefox (no drop-down, no coordinates, no position on the map).
The map page on the other hand is only available inside Firefox (which is fine, as I use that browser anyway).
I checked this issue but on my browser is working. Could you try again please? If it is not working, please give me more details like the errors in the Developer Tool if you can.