Why i cannot access sap b1 app on mobile android


I successfully install Pritunl VPN on Ubuntu Hyper-V and i can actually connect using the VPN client on my desktop I can open sap web client on my browser but the problem I am facing is when I install OpenVPN on my Android I can connect successfully but I cannot open the webclient app on my android. The funny thing is I have no issue with desktop and laptop only with mobile… is there any solution on this please help