Sharepoint 2019 On-Prem OneDrive

Dear Community,

in our company we operate a Sharepoint 2019 On premise for external connection. Now the wish was expressed that data should be synchronized offline using OneDrive.

I was able to recreate the actual system with a test system. The user profile service, mysitehost and the Gpo were configured correctly. Also OneDrive is up to date.

But now I have the problem that OneDrive tells me that the login went wrong.

I hope you can help me and give me a few more starting points for solutions. thank you