diff --git a/backend/services/referral-service/src/infrastructure/kafka/event-ack.publisher.ts b/backend/services/referral-service/src/infrastructure/kafka/event-ack.publisher.ts
index d9962bd9..f2fb1fc9 100644
--- a/backend/services/referral-service/src/infrastructure/kafka/event-ack.publisher.ts
+++ b/backend/services/referral-service/src/infrastructure/kafka/event-ack.publisher.ts
@@ -48,7 +48,7 @@ export class EventAckPublisher {
       await this.kafkaService.publish({
         topic: 'planting.events.ack',
         key: eventId,
-        value: ackMessage,
+        value: ackMessage as unknown as Record<string, unknown>,
       });
 
       this.logger.log(`[ACK] ✓ Sent success confirmation for event ${eventId} (${eventType})`);
@@ -74,7 +74,7 @@ export class EventAckPublisher {
       await this.kafkaService.publish({
         topic: 'planting.events.ack',
         key: eventId,
-        value: ackMessage,
+        value: ackMessage as unknown as Record<string, unknown>,
       });
 
       this.logger.warn(`[ACK] ✗ Sent failure confirmation for event ${eventId}: ${errorMessage}`);