When you push a payment to your ERP and it fails partway through (for example, due to a duplicate discount that should have been zeroed out, or another line-level error), you may notice that a credit memo was still created in your ERP even though the payment itself did not go through.
This happens because of the order Confido uses when pushing a payment: the credit memo covering the deductions is created first, and the payment application happens second. If an error occurs during the payment application step, the credit memo has already been posted to your ERP — Confido does not automatically roll it back.
To resolve
In your ERP, locate the credit memo that was created for the failed push (it will typically match the invoice/customer referenced in the error).
Reverse or delete that credit memo directly in your ERP.
Fix the underlying issue in Confido (e.g. correct the discount amount or remaining balance) so the payment shows as "good to go."
Re-push the payment from Confido.
Note: Because credit memo creation happens before payment application, it is not currently possible to configure Confido to hold back credit memo creation until the payment step succeeds.