Trying to Import an XML file into a MS SQL table using PowerShell - sql-server

Question

I am trying to import an XML file into a MS SQL table using PowerShell, I have modified a PowerShell script I already had that worked fine but could do with some help as the new XML file has multiple entries for some elements.( I have included a sample of the XML file)
Table layout is below and as is a sample of the file I am trying to import and also my script I am trying to modify to get working.
Table layout is:
------------------------------
:supplier_id : name : Symbol :
and here is an part of the XML file itself
<SupplierMapping supplier_id="4536" name="Joby">
<Symbol>Joby</Symbol>
</SupplierMapping>
<SupplierMapping supplier_id="4537" name="ACT">
<Symbol>ACT</Symbol>
<Symbol>ADVANCED CABLE TECH</Symbol>
<Symbol>ADVANCED CABLE TECHNOLOGY</Symbol>
<Symbol>IEC LOCK</Symbol>
</SupplierMapping>
As you can see some supplier id's and names will have multiple <Symbol> names so I would like to have multiple entries in my table for those, however the script I have modified only seems to pull in the supplier_id and name elements and misses the <Symbol> part entirely. any help or guidance would be much appreciated.
Set-ExecutionPolicy Unrestricted -Scope LocalMachine
[String]$global:connectionString = "Data Source=Apps2\Apps2;Initial Catalog=DTEDATA;Integrated Security=SSPI";
[System.Data.DataTable]$global:dt = New-Object System.Data.DataTable;
[System.Xml.XmlTextReader]$global:xmlReader = New-Object System.Xml.XmlTextReader("C:\Scripts\icecat\supplier_mapping.xml");
[Int32]$global:batchSize = 100;
function Add-FileRow() {
$newRow = $dt.NewRow();
$null = $dt.Rows.Add($newRow);
$newRow["supplier_id"] = $global:xmlReader.GetAttribute("supplier_id");
$newRow["name"] = $global:xmlReader.GetAttribute("name");
$newRow["Symbol"] = $global:xmlReader.GetAttribute("Symbol");
}
# init data table schema
$da = New-Object System.Data.SqlClient.SqlDataAdapter("SELECT * FROM Supplier_Mapping_Test WHERE 0 = 1", $global:connectionString);
$null = $da.Fill($global:dt);
$bcp = New-Object System.Data.SqlClient.SqlBulkCopy($global:connectionString);
$bcp.DestinationTableName = "dbo.Supplier_Mapping_Test";
$recordCount = 0;
while ($xmlReader.Read() -eq $true) {
if (($xmlReader.NodeType -eq [System.Xml.XmlNodeType]::Element) -and ($xmlReader.Name -eq "SupplierMapping"))
Add-FileRow -xmlReader $xmlReader;
$recordCount += 1;
if (($recordCount % $global:batchSize) -eq 0) {
$bcp.WriteToServer($dt);
$dt.Rows.Clear();
Write-Host "$recordCount file elements processed so far";
}
}
}
if ($dt.Rows.Count -gt 0) {
$bcp.WriteToServer($dt);
}
$bcp.Close();
$xmlReader.Close();
Write-Host "$recordCount file elements imported ";
catch {
throw;
}