Good day Njabulo, 

It is not possible to process journal entries to system accounts. **system accounts** populate based on the transactions that you have processed. so to correct a system account "amount" you would have to correct the original transaction which was processed.

**example**: if you need to decrease **sales** you would either **edit** the customer invoice which was processed or credit note and re-invoice with the correct details.

journal entries, however, are available for customers and suppliers (customer adjustments and supplier adjustments).

Please visit our Knowledge Base article link for guidance on how to process customer adjustment
https://za-kb.sage.com/portal/app/portlets/results/viewsolution.jsp?solutionid=200116122201361&page=1&position=1&q=how%20to%20process%20customer%20adjustment&guest=0

Please click on our Knowledge Base article for more information on how to process a supplier adjustment

https://za-kb.sage.com/portal/app/portlets/results/viewsolution.jsp?solutionid=200127142930246&page=1&position=1&q=supplier%20adjustment

Regards,