UV Overlapping Issues

Hello!
I have a little problem with a few objects.
“Object has overlapping UVs.” " Lightmap UV are overlapping by 8.6 % Please adjust content."

To solve this problem I followed this tutorial. Unfortunately this did not solve my problem.

Bildschirmfoto von 2023-01-19 14-58-26

Does anyone have any idea what this could be or how I could fix it?
Kind regards