I read a lot abaout this problem but I couldn't find an answer. Whenever I want to edit something for example, I get the 'Diese Funktion ist in Ihrer aktuellen Acrobat-Lizenz nicht vorhanden.'-message which translates to 'This function is not availabe in your current Acrobat-licence.' even tough I registered with the correct serial number when installing the program. Whenever I open Acrobat Pro 2020, I am just able to see the document but I am not able to do anything else.

Adobe Acrobat XI Pro comes with smart features that provide additional interoperability. When creating your PDF files and processing them in the future, Adobe Acrobat becomes absolutely irreplaceable. Before I bought the program I used the free trial version and now it says in the left down corner that my licence is no longer vailable. Acrobat XI Pro includes advanced functions that open many additional functions, quite easy to manage, it has a friendly interface. I am a teacher and had my product registered correctly. (picture attaced) The error message I get is also attached. I installed the program that is in my profile after I registered it there. I use a MacBook Pro macOS Big Sur Version 11.4. I installed the program just as described and I reinstalled it again after reading that this could help.

Adobe 2020 pro