Do Help > System Info that you are running LR CC 2015.6.1. If you're running an earlier version, do Help > Updates to update to the latest version. Some earlier versions of LR CC had a couple of bugs with the map module on Windows.
If that doesn't help, uncheck the option Preferences > Performance > Use Graphics Processor. Even though the GPU is only supposed to be used in the Develop module, there have been a few reports that disabling it fixed display problems with the Map module (and other modules).
Finally, check that you have the most recent driver for your graphics chipset by downloading it directly from the manufacturer's Web site: Adobe Lightroom GPU Troubleshooting and FAQ
Thanks for the suggestions. I have version 6.6.1, have unchecked graphic processor and have also latest driver installed.
No change. The funny thing is that a part of the map is appearing, part of it is black and the visible part is mainly upside down.
When I open Google Maps in a browser, these maps are ok.