Change storage account Azure tier to archive

$resourcegroup="archiwum"
$StorageAccount="archiwumzdjecsa"
$container="zdjecia"
$stgkey=((Get-AzStorageAccountKey -ResourceGroupName $resourcegroup -Name $StorageAccount)[0]).Value
$ctx =New-AzureStorageContext -StorageAccountName $StorageAccount -StorageAccountkey $stgkey
$blob= Get-AzureStorageBlob -Container $container -Context $ctx |  where AccessTier -ne "Archive"
$blob.ICloudBlob.SetStandardBlobTier("Archive")