Remove the green wire from the frame and insulate it. The green wire from the cord goes to the frame of the dryer. The power ground wire from the cord goes to the middle terminal of the dryer connector. Power ground and frame ground must be electrically disconnected.

I assume you are wiring a dryer for 230 operation.The dryer green wire is attached to the power ground middle pin of the connector. You want power ground from the cord isolated from the frame of the dryer.
The cord green wire is isolated from the power line ground and goes to earth ground. If lightning strikes the power wires, you want that isolated from the frame of the dryer for obvious reasons.
If lightning strikes the wires, before they fuse open from the large current to ground, they will elevate power ground to thousands of volts. You want the frame of the dryer to be shielded from this.
If you go to your home breaker box, you will see the white wire going to power ground inside the box which is wired to the frame of the box. A separate copper wire goes from this to a clamp on a cold water pipe. This wire is relatively thin, like 12 guage and will probably be the wire that fuses open in a lighting strike.
You will see a green insulated wire which should be going outside to an iron pipe that is pounded in the ground. This is the earth ground that goes to the dryer frame.