new field added in fieldset.xml

Author: mahesh-rajawat

app/code/Magento/Quote/Model/Quote/Item/ToOrderItem.php

@@ -64,7 +64,14 @@ public function convert($item, $data = [])
             $item
         );
         if ($item instanceof \Magento\Quote\Model\Quote\Address\Item) {
-            $orderItemData['quote_item_id'] = $item->getQuoteItemId();
+            $data = array_merge(
+                $data,
+                $this->objectCopyService->getDataFromFieldset(
+                    'quote_convert_item',
+                    'to_order_item_id',
+                    $item
+                )
+            );
         }
         if (!$item->getNoDiscount()) {
             $data = array_merge(

app/code/Magento/Quote/etc/fieldset.xml

@@ -205,6 +205,9 @@
             <field name="qty">
                 <aspect name="to_order_item" targetField="qty_ordered" />
             </field>
+            <field name="quote_item_id">
+                <aspect name="to_order_item_id" targetField="quote_item_id" />
+            </field>
             <field name="id">
                 <aspect name="to_order_item" targetField="quote_item_id" />
             </field>