@sitloongs thank you for the information. Seems that I had forgotten about allowing the MS-CHAP-V2 on windows.
On macOS Mojave 10.14.3 however, I followed the guide, and connection drops when you have send all internet traffic over VPN checked with the following error : You were disconnected because the PPP server is not responding. Try reconnecting…
When I unchecked send all traffic through vpn I have a success connection and no drops so far.
Why would this be?