Using world map plugin with prometheus


I’m using Grafana with Prometheus and want to use the World Map plugin: the idea is that I have several geopoints with some values that I want to visualize with World Map.

Data example that is being returned from prometheus has the following structure:

Also I edit probes.json and 100% shure that World Map plugin is using my customized probes.json file. Here is the part of it:
“key”: “taipei”,
“latitude”: 25.105497,
“longitude”: 121.597366,
“name”: “Taipei”
“key”: “tokyo”,
“latitude”: 35.652832,
“longitude”: 139.839478,
“name”: “Tokyo”
“key”: “y1918”,
“latitude”: 53.717564,
“longitude”: 91.429317,
“name”: “ABAKAN”
“key”: “szvpz”,
“latitude”: 44.993166,
“longitude”: 41.103135,
“name”: “ARMAVIR”
“key”: “ugkz7”,
“latitude”: 64.5562829,
“longitude”: 40.5962809,
“key”: “v04pt”,
“latitude”: 46.3432541,
“longitude”: 47.933211,
“name”: “ASTRAKHAN”

Here is the Grafana setup:

I get no error but there is no circles on the map, what am I doing wrong? What data should I provide to grafana from prometheus if it is the reason of the problem I’m having? Adding Legend format “{{geohash}}” doesn’t help either.