curl -X POST "https://olive-gateway-a6ba.onrender.com/api/v1/cards/OLIV0001/block" \
  -H "Authorization: Bearer olive_live_xxx" \
  -H "Content-Type: application/json" \
  -d '{
    "reason": "Lost card - customer reported",
    "pin": "1234"
  }'

{
  "success": true,
  "message": "Card blocked successfully",
  "card": {
    "serial": "OLIV0001",
    "status": "BLOCKED",
    "blocked_at": "2025-01-20T14:45:00Z",
    "blocked_by": "admin@olive.sl",
    "block_reason": "Lost card - customer reported"
  }
}