Azure: Failed to save configuration changes to local network gateway

Seems you can’t remove a subnet from a local network with the Azure portal. Error: “Failed to save configuration changes to local network gateway”

To get around this, I had to delete and recreate the local network via PowerShell. Obviously leave out the subnet you don’t want!

Get-AzureRmLocalNetworkGateway -Name "HomeOffice" -ResourceGroupName "WestUS"
$localNetworkGw=Get-AzureRmLocalNetworkGateway -Name "HomeOffice" -ResourceGroupName "WestUS"
$addressPrefixes ="192.168.0.0/24","192.168.1.0/24","192.168.2.0/24","192.168.4.0/24"
Set-AzureRmLocalNetworkGateway -LocalNetworkGateway $localNetworkGw -AddressPrefix $addressPrefixes -Verbose