Sales and Purchase transactions use Analysis records when posting to the Nominal ledger and so it will be necessary to check the one(s) used, and make amendments if required:
Identify which analysis record was used for the incorrect posting(s) via the transaction detail in the relevant Enquiry Screen.
In Debtors/Creditors, click Analysis from the ribbon.
Find the appropriate analysis and review the codes it is posting to.
Note: Analysis records use the transaction type as well as Debit and Credit account information when posting so a code may look as though it is the wrong way around but actually be correct. There is more information available about setting up analysis records.
Click Open, Edit and Save the record to make any changes necessary.