Dear Antonio,
Follow the below steps.
1. Go to Business Configuration work center
2. Select Implementation Projects
3. Select Open Activity List > Fine Tune
4. Find Charts of Accounts, Financial Reporting Structures, Account Determination & select < Open >
5. Select Sub-ledger < Sales >
Now the fields are editable when you click on "Add row"
Hope this is helpful for you. Please confirm this thread.
Thanks
Lokesh Sharma
