8. EHI Message Identification Guidance

Your system may receive different types of EHI messages depending on the transaction lifecycle event.

Your system should identify the message type using the EHI fields included in the forwarded payload, especially `MTID`, `Txn_Type`, `Txn_Stat_Code`, `CutOffId`, and related lifecycle identifiers.

EHI notifications include authorizations, presentments, financial messages, and other payment-related messages. Response behavior depends on the message type.

8.1 Main message categories

8.2 How to identify messages

Your system should use the EHI fields to determine how to process each message.

8.3 Processing expectations

Your system should not treat every EHI message as a new authorization.

Instead, your system should first identify the message type and then apply the correct processing path.

• Decisional message – Return the required authorization decision within the processing window.

• Non-decisional message – Acknowledge receipt and process the message for transaction history, ledger updates, or reconciliation.

• Reversal message – Match the reversal to the original transaction and release, reverse, or adjust the previous transaction impact.

• Financial or presentment message – Match the message to the related authorization when possible and post or reconcile the final transaction.

• Duplicate or retry message – Return the same logical response as the original processing and avoid duplicate balance, block/reserve, or ledger impact.

• Cut-off message – Process the cut-off summary and return Cut_OffResult.

Important note: Your system should apply the EHI message type logic using the payload fields exactly as received. The detailed transaction-specific sections that follow explain how each message type should be handled, matched, and answered.