Cannot deactive license for SDL Trados Studio 2017 Freelance Plus

I am trying to deactivate the second license for this product. I received an error message for online activation, tried to do offline activation but couldn't generate a certificate and received the error message: "An error has occurred with your offline-deactivation. If you continue to have problems, please Please log a support request."

Could someone please help? I need to deactivate the licence activated on 10-01-2023, but please keep the licence from 13-09-2017 active.