Hi,
Most applications can't detect that it's virtual machine or not. But they can detect your virtual machine's sockets by OS APIs.
So if you application's license is socket base. You should reduce your virtual machine's sockets.
I suggest you to use 1 socket and 4 cores. Maybe you're using 4 sockets and 1 core.
Check your VM configuration and if possible, please send a screen shot from that.