FI/CO interface: Balance in transaction currency

What causes this issue?

The balances in transaction currency must be zero for each logical
transaction when transferring to the FI/CO interface. A balance of
"&v2&" "&v3&" was determined for the logical transaction "&v1&".

System Response

The FI/CO interface does not process any transactions which have a
balance in transaction currency other than zero.

How to fix this error?

This is a system error of the calling application.

Error message extract from SAP system. Copyright SAP SE.