Nothing in the Nacha rules mandates a financial institution must file a rules violation report...now, if an originator not acting on NOCs is causing your bank grief, in that you are having to manual process transactions because of the incorrect account numbers, you certainly can choose to file one. You could also do as suggested above and contact your client. and also contact the ODFI. if both of those attempts fail, certainly within your rights to file a rules violation.
of course, returning the transaction as "no account found" is also an option. But one that severely impacts your customer, and is a pretty drastic measure.
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