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Portico Developer Guide
Managing Timeout Scenarios
Special Processing Rules > Incremental Authorization > Managing Timeout Scenarios

CreditReversal is not supported for incremental authorizations.  If a response is not received for an Incremental authorization request, ReportTxnDetail or FindTransactions can be used to verify whether it was received by the host. A card present POS may repeat the incremental authorization.  The original can be voided or reversed, and a new Credit Auth processed for the updated amount.