External Host Interface Integration Guide
15. Transaction Lifecycle Overview
EHI messages should be processed as part of a transaction lifecycle, not as isolated events.
As with all EHI messages, Payblr forwards each EHI JSON payload to your configured endpoint. Your system is responsible for identifying the message type, matching it to related transactions when possible, and applying the correct balance, block/reserve, ledger, dispute, and reconciliation logic.
Not every transaction follows the same lifecycle. Some transactions may only include an authorization and presentment. Others may include advice messages, reversals, financial reversals, chargebacks, or retries.
Your system should use the EHI fields, such as MTID, Txn_Type, Token, TXn_ID, Txn_ID, traceid_lifecycle, Trans_link, Auth_Code_DE38, Acquirer_Reference_Data_031, and CutOffId, to determine how each message should be processed.
15.1 Standard transaction lifecycle
The lifecycle below shows a typical transaction flow from authorization through financial posting and reconciliation.
Standard transaction lifecycle
Platform
Payblr
System
Your Systems
15.2 Lifecycle stages
| Lifecycle stage | Message type | Purpose | Expected handling by your system |
|---|---|---|---|
| Authorization decisioning | 0100 / A | Request an authorization decision | Approve, decline, or partially approve based on your internal rules. |
| Authorization repeat | 0101 / A | Repeat or retry an authorization-related message. | Match to the original authorization and return the same logical response when possible. |
| Authorization advice | 0120 / J | Notify your system of an authorization-related event | Match to the original authorization and update block, balance, ledger, or reconciliation records. |
| Authorization reversal | 0120 / D advice / 0400 / D / 0420 / D | Reverse or adjust a previous authorization impact. | Match to the original authorization and release or adjust the blocked amount. |
| Financial / presentment | 1240 / P, 05pp / P, 06pp / P, 07pp / P | Post or reconcile the final financial transaction. | Match to the authorization when possible, release related block, and post or reconcile the transaction. |
| Financial reversal | 1240 / E, 25pp / E, 26pp / E, 27pp / E | Reverse or adjust a previous financial posting. | Match to the prior financial notification and reverse or adjust the posted impact. |
| Chargeback | 1240 / C, 1240 / H | Notify your system of a dispute-related financial event | Update dispute, ledger, transaction history, and reconciliation records. |
| Chargeback reversal | 1240 / K | Reverse or adjust a previous chargeback impact. | Match to the original chargeback when possible and reverse or adjust the chargeback-related impact. |
| Cut-off | CutOffId | Support cut-off and reconciliation processing. | Process using CutOffId and return the required Cut_OffResult. |
15.3 Message classification rules
Your system should first identify the message type before applying any transaction logic.
When a message is received, your system should:
- Check whether the payload contains
CutOffId. - If
CutOffIdis present, process the message as a cut-off message. - If
CutOffIdis not present, identify the message usingMTIDandTxn_Type. - Determine whether the message requires a real-time decision, acknowledgement, reversal handling, posting, dispute handling, or cut-off response.
- Apply the correct matching criteria for the message type.
- Check whether the message was already received or processed.
- Apply only the appropriate balance, block/reserve, ledger, dispute, or reconciliation impact.
- Return the required
JSONresponse.
15.4 Lifecycle decision guide
| If the message is... | Your system should... |
|---|---|
| An authorization decisioning message | Return the required authorization decision within the processing window. |
| An authorization repeat | Match to the original authorization and return the same logical response when possible. |
| An authorization advice | Match to the original authorization when possible and update transaction records, blocks, balances, or reconciliation status. |
| An authorization reversal | Match to the original authorization and release or adjust the previous authorization block. |
| A financial / presentment message | Match to the related authorization when possible, release related block, and post or reconcile the final transaction. |
| A financial reversal | Match to the prior financial notification and reverse or adjust previous posted financial impact. |
| A chargeback | Update dispute, ledger, transaction history, and reconciliation records. |
| A chargeback reversal | Match to the original chargeback when possible and reverse or adjust the chargeback-related impact. |
| A duplicate or retry | Return the same logical response as the original processing and avoid duplicate impact. |
| A cut-off message | Process using CutOffId and return Cut_OffResult. |
| An unmatched message | Store the message and route it to reconciliation or exception handling. |
15.5 Unmatched lifecycle events
Some messages may arrive without a matching prior transaction in your system.
Examples include:
- Authorization advice without a matching original authorization.
- Authorization reversal without a matching authorization.
- Presentment without a matching authorization.
- Financial reversal without a matching financial notification.
- Chargeback without a matching financial notification.
- Chargeback reversal without a matching chargeback.
When this happens, your system should:
- Store the unmatched message.
- Return the required acknowledgement response, unless the message type requires a different response.
- Route the message to reconciliation or exception handling.
- Avoid applying unsupported or duplicate balance, block/reserve, ledger, or dispute impact.
- Preserve the EHI fields so the message can be investigated later.