diff --git a/backend/services/deploy-mining.sh b/backend/services/deploy-mining.sh
index 438c0202..b63d4a54 100755
--- a/backend/services/deploy-mining.sh
+++ b/backend/services/deploy-mining.sh
@@ -927,7 +927,7 @@ full_reset() {
         fi
     done
 
-    log_step "Step 4/18: Deleting Debezium outbox connectors..."
+    log_step "Step 4/18: Deleting Debezium outbox connectors and Kafka topics..."
     # Delete connectors BEFORE dropping databases to release replication slots
     local connectors=("auth-outbox-connector" "contribution-outbox-connector" "mining-outbox-connector" "trading-outbox-connector" "mining-wallet-outbox-connector")
     for connector in "${connectors[@]}"; do
@@ -937,6 +937,18 @@ full_reset() {
     log_info "Waiting 5 seconds for connectors to be fully removed..."
     sleep 5
 
+    # Delete Kafka outbox topics to clear old messages
+    # This is critical: old messages in Kafka will corrupt the sync if not cleared
+    log_info "Deleting Kafka outbox topics to clear old messages..."
+    local outbox_topics=("cdc.auth.outbox" "cdc.contribution.outbox" "cdc.mining.outbox" "cdc.trading.outbox" "cdc.mining-wallet.outbox")
+    for topic in "${outbox_topics[@]}"; do
+        if docker exec "$KAFKA_CONTAINER" kafka-topics --bootstrap-server localhost:9092 --delete --topic "$topic" 2>/dev/null; then
+            log_success "Deleted Kafka topic: $topic"
+        else
+            log_warn "Could not delete Kafka topic: $topic (may not exist)"
+        fi
+    done
+
     log_step "Step 5/18: Dropping 2.0 databases..."
     db_drop