Hey @dennisdonk to unlink a PSN account from an EA account you would need to speak with one of our phone or chat support advisers who will be able to advise you further.
You can contact our live support at help.ea.com.
To request a callback or speak with a chat adviser:
Click on your product Origin
Then select 'PC
Manage my Account'
Can't log in
Finally, you can choose to receive a callback or begin a chat.