Create client vpn package before or after upload root certificate

Hi everyone,

I am building funtion create client vpn package base on os bit (64 or 32) to connect point to site of azure virtual network

I want to ask somebody 

Create client vpn package before or after upload root certificate?

If i upload root certificate, funtion return error 404

if i do not upload root certificate and run funtion generate

funtion return status code is accept

correct resuft follows msdn is created

althought request body is correct

ResponseUri = {https://management.core.windows.net/29976d9e-898b-46ab-9f80-6238b4f1725e/services/networking/quyen_network/gateway/vpnclientpackage}

<VpnClientParameters><ProcessorArchitecture>Amd64</ProcessorArchitecture></VpnClientParameters>
Thanks for you supports,
Hoa Nguyen