Why Map visual does not display data for one voivodship (district?)

Hi Fistachpl 

I have got some feedback. 

Map visuals use similar geocoding endpoints to match written language description to geographical entities. The (old) Bing Maps and (new) Azure Maps endpoints are little different. Since geocoding results could be different based on the culture of the current user, the geocoding queries also provide the users' current locale.  This could be the system's locale settings if using Desktop, or browser-specific locale settings if using the Service. Please ensure that the locale settings of the system + browser (if applicable) are supplying the "pl-PL" locale.

Additionally, Power BI plans to deprecate older Bing map visuals and migrate existing reports to Azure Maps in a future release. Azure Map visual is more encouraged if it works better and fits your use case. In my test, the Azure Map visual won't miss any voivodeship of Poland. Can you try if the Azure Map visual works better at your case? Here is a documentation for your reference: Filled map in Azure Maps Power BI Visual - Microsoft Azure Maps | Microsoft Learn

Best Regards,
Jing