For example:

Example input data looks like:
1,12345,7654321,1,08/08/19,08/08/19
2,12345,12345678,3
2,12345,22345679,7
2,12345,32345680,6
2,12345,42345681,2
3,12345,

What the data looks like from a human perspective:
First line, ID, accountNo, ???, orderDate, orderDate
Product row, ID, productCode, quantity
Product row, ID, productCode, quantity
Product row, ID, productCode, quantity
Product row, ID, productCode, quantity
Last Line, ID,

Output should be something like:

<?xml version="1.0"?>
<orders><order accountNo="7654321" orderDate="08/08/19"><orderItems><orderItem productCode="12345678" quantity="3"/><orderItem productCode="22345679" quantity="7"/><orderItem productCode="32345680" quantity="6"/><orderItem productCode="42345681" quantity="2"/></orderItems></order></orders>