A BACS message may be ignored rather than processed by the system if the existing details provided in the message don't match the details held in Access PaySuite DDCMS.
It's likely to happen if, for instance, you've manually updated a payer's bank details in Access PaySuite DDCMS, and an ADDACS code is subsequently received relating to the previous details. There's normally no action you need to take as long as you're satisfied the details held for the payer on Access PaySuite DDCMS are correct.
Please see our guide on ADDACS reason codes for more information.