title: magento duplicate block twice in page sales order view
body: <p>I have an installation of <code>magento 1.9.2.1</code>, I have a duplicate block rendering in some pages this is the code used in my custom theme <code>sales.xml</code>:</p>
  
  <pre><code>&lt;sales_order_view translate="label"&gt;
      &lt;label&gt;Customer My Account Order View&lt;/label&gt;
      &lt;update handle="customer_account"/&gt;
      &lt;reference name="my.account.wrapper"&gt;
          &lt;block type="sales/order_info" as="info" name="sales.order.info"&gt;
              &lt;block type="sales/order_info_buttons" as="buttons" name="sales.order.info.buttons" /&gt;
          &lt;/block&gt;
          &lt;block type="sales/order_view" name="sales.order.view"&gt;
              &lt;block type="sales/order_items" name="order_items" template="sales/order/items.phtml"&gt;
                  &lt;action method="addItemRender"&gt;&lt;type&gt;default&lt;/type&gt;&lt;block&gt;sales/order_item_renderer_default&lt;/block&gt;&lt;template&gt;sales/order/items/renderer/default.phtml&lt;/template&gt;&lt;/action&gt;
                  &lt;action method="addItemRender"&gt;&lt;type&gt;grouped&lt;/type&gt;&lt;block&gt;sales/order_item_renderer_grouped&lt;/block&gt;&lt;template&gt;sales/order/items/renderer/default.phtml&lt;/template&gt;&lt;/action&gt;
                  &lt;block type="sales/order_totals" name="order_totals" template="sales/order/totals.phtml"&gt;
                      &lt;action method="setLabelProperties"&gt;&lt;value&gt;colspan="2" class="a-right"&lt;/value&gt;&lt;/action&gt;
                      &lt;action method="setValueProperties"&gt;&lt;value&gt;class="last a-right"&lt;/value&gt;&lt;/action&gt;
                      &lt;block type="tax/sales_order_tax" name="tax" template="tax/order/tax.phtml" /&gt;
                  &lt;/block&gt;
              &lt;/block&gt;
          &lt;/block&gt;
      &lt;/reference&gt;
      &lt;reference name="sales.order.info"&gt;
          &lt;action method="addLink" translate="label" module="sales"&gt;&lt;name&gt;view&lt;/name&gt;&lt;path&gt;&lt;/path&gt;&lt;label&gt;Order Information&lt;/label&gt;&lt;/action&gt;
          &lt;action method="addLink" translate="label" module="sales"&gt;&lt;name&gt;invoice&lt;/name&gt;&lt;path&gt;*/*/invoice&lt;/path&gt;&lt;label&gt;Invoices&lt;/label&gt;&lt;/action&gt;
          &lt;action method="addLink" translate="label" module="sales"&gt;&lt;name&gt;shipment&lt;/name&gt;&lt;path&gt;*/*/shipment&lt;/path&gt;&lt;label&gt;Shipments&lt;/label&gt;&lt;/action&gt;
          &lt;action method="addLink" translate="label" module="sales"&gt;&lt;name&gt;creditmemo&lt;/name&gt;&lt;path&gt;*/*/creditmemo&lt;/path&gt;&lt;label&gt;Refunds&lt;/label&gt;&lt;/action&gt;
      &lt;/reference&gt;
      &lt;block type="core/text_list" name="additional.product.info" translate="label"&gt;
          &lt;label&gt;Additional Product Info&lt;/label&gt;
      &lt;/block&gt;
  &lt;/sales_order_view&gt;
  </code></pre>
  
  <p>If anybody has an idea about the origin of this thank you for help.</p>