Stream VPN use a different username to log in to their website and to use their VPN with OpenVPN. This is why the username you use to log in to the Stream VPN website will not work on your InvizBox.
Click the following link to log in:
Once logged in, you can find your VPN username under the "VPN Username" column
This is the username you will need to use in your InvizBox 2.
The password will be the same as you use to log in to the "Stream VPN" website.
Next, connect to your InvizBox WiFi and login to your InvizBox administration interface using either the administration app, or by browsing to http://inviz.box
You can find out where to enter these VPN credentials on your InvizBox 2 in this article.