curl --request GET \
  --url https://api.speedsellx.io/seller/v1/subscriptions/{id}

{
  "data": {
    "id": 123,
    "status": "<string>",
    "order_id": 123,
    "customer_id": 123,
    "interval": "<string>",
    "interval_count": 123,
    "start_date": "<string>",
    "end_date": "<string>",
    "expires_at": "<string>",
    "created_at": "<string>"
  }
}