OpenStreetMap in Unity Map bug

Hello guys,
in the last days I have followed a youtube tutorial to create in Unity maps from Open Street Map data.
My problem is that the map always looks like this and is flickering around if I move my camera:



I have already tried to use the same unity version like in the tutorial and downloaded the original source code but still its not working? Are there any settings in my unity version wrong or any other wrong software?

Here you can find the tutorial:

And here you can find the github project: https://github.com/codehoose/real-world-map-data

 

I have the same problem, did you find an answer?

 

maybe you requested too large area?
then mesh needs 32bit index (if the script doesn't do that already?)
https://docs.unity3d.com/ScriptReference/Mesh-indexFormat.html

 

https://github.com/codehoose/real-world-map-data/issues/6