I want to create an UV Map for each of my materials and it's somehow not working. Currently I'm working on a shopping mall for Cities: Skylines. I've assigned all faces with materials, and with those materials, I want to UV Map them separately, because it would be too much work to UV Map everything into one single map.
As you can see, the materials are set and ready to be uv-mapped.
Now when I create a new UV-Map, the old one is still showing up as you can see in the picture right above. Is there a way to create a new UV-Map, without the old uv-map showing up? Any other advice to texturing or uv-mapping this shopping mall also will be helpful for me. I just don't want to spend thousands of hours trying to unwrap this project. Thanks

Unwrap, this timeUV Export LayoutandOpen. I ended up on very different UV map and still, it is not applied to the object :-(. – Oak_3260548 Jul 25 '22 at 19:20