Hi @Rene Wagner
I'm glad to hear you solve the problem ,if you have any issue about SharePoint, you are welcome to raise a ticket in this forum.
By the way, since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others.". and according to the scenario introduced here: Answering your own questions on Microsoft Q&A, I would make a brief summary of this thread:
Issue configuring multiple Managed Metadata Service Applications
Issue Symptom:
when access the service applications in Central Admin (no matter which one I click on), both will display the same term store entries, and the "Available Service Applications" drop down (where I am supposed to be able to select which term store I want to see) only contains an option for the default Managed Metadata Service application.
Current status:
Due to deselected the option "Add this service application to the farm's default list"
This issue has been resolved
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