3D modeling background preview doesnt work well

Hello.

I am in a trouble for that issue in dynamo.

It supposted to be showed a Tunnel model.

but Only one thing i can see is points and Line/curve.

Of cource i turn on the ‘3D background preview’ menu.

installed Direx X 12/and Nvidia control panel.

but finally it doesnt work well.

My computer has a system as below.
i7/64gb/window10/nvidia gtx 1060 6gb

Anyone can help me? if so. Thanks you so much in advance.