POST /webhooks/payblr/ehi HTTP/1.1 Host: api.client.example Content-Type: application/json User-Agent: payment-service-platform-functions/ehi X-EHI-Signature: bbda8f32036f959120590d49c5b855744e044129cd8c0b517eb66a005a6414fc X-EHI-Signature-Algorithm: hmac-sha256 X-EHI-Signature-Timestamp: 1780272000000 X-Correlation-Id: client-test-correlation-001 {"ProductID":"CLIENT-CARD-001","MTID":"0100","Txn_Type":"A","Txn_ID":"TXN-20260601-000001","Amount":1250,"Currency":"USD"}