I am from Brazil too and I can't complete conection VPN PPTP using de hotspot of my S9. Internal VPN of phone works fine.
With Note9 of my boss is the same.
Samsung support where are you?
Same problem here. It's a serious restriction and inadmissible for such an expensive phone. I use it diary and this problem makes the phone almost useless.
Come on Samsung...
With help of a IT company of support we start to using openVPN. Of course is not a solution, but a tip for who have extreme necessity os VPN connection, like us.
So Apple and Andriod operating systems have removed the ability to PPTP using hotspot as they advised its a old protcol and to use a different protocol. If you are VPN into work server your IT department will need to enable CHAP or PAP in Routing and Remote Access on the server so you can VPN hope this help you all