Cause
When printing statements, it is verified that the totals of all the invoices grouped by customer correspond to the balances of the account cards of the respective customers. If the amounts do not match, the difference is reported.
Solution
Compare the movements of the customer's account card with the customer-related invoices. Usually these warnings occur as a result of other errors reported during printing, for example the presence of exchange differences or for the use of VAT with a currency other than the customer's currency.