Effective date: 16 March 2026
Overview
We're adding a new field to the transaction callback payload to include the product name alongside the existing product code. This is an additive, backward-compatible change. No request parameters, status codes, or existing callback fields are affected.
Callback methods impacted:
- POST callback
- GET callback
What's changing
New field in the callback payload under data:
"data": {
"product": "CELCOM", // existing field
"productName": "Celcom Prepaid", // new String field
...
}
productName (string): The human-readable display name for the product associated with the transaction. This field already exists in the POST /v2/topup response and will now also be included in the callback payload.
Backward compatibility
- Non-breaking; existing fields and their formats are unchanged.
- productName is additive only. Callbacks that previously parsed will continue to parse.
- If you use strict JSON schema/model validation, update your models to include productName or configure them to ignore unknown properties.
Actions for integrators
- No action required to maintain existing functionality.
- Optional: You can now use productName from the callback payload directly to display product names in your callback-driven flows, eliminating the need to maintain a separate product code-to-name mapping.
Should you require any further assistance or additional information, please do not hesitate to reach out to us via email at support@iimmpact.com




