Px4 dual gps error

Hi, I am using Pixhawk 2.1 Cube and PX4. I have a two GPS. There are Hex Here and Hex Here2. I’m connecting the Hex Here through the GPS1 port. I’m connecting the Hex Here2 through the CAN1 port. What parameters do we need to change in QGroundcontrol? We are unable to run 2 GPS at the same time.

Thanks