You sent a transaction with an incorrect transaction code (i.e., you meant to send a credit, but you actually sent a sale or you meant to process a sale and sent a credit).
For more information, please see Dispute Management Guidelines for Visa Merchants.
Acquirer’s approach or timelines may be different and you should adhere with your current Acquirer’s process. Not all disputes apply to every country/region, please check with your acquirer for further information.