New to qubes - Creating a new VM as NetVM

Aren’t your network devices already assigned to the existing sys-net qube? Have a look at the qube Settings/Devices in Qube Manager. If yes, you can also assign them to another qube, but you can’t run these two qubes simultaneously. If they aren’t anywhere, you may have a problem with the drivers/firmware. Which laptop are you using? (On recommended machines, everything works out of the box.)