This is not a problem with Dgraph, but with your use of the useMutation return function.
deleteProduct({ filter: { id: device.id } })
Should be
deleteProduct({ variables: { filter: { id: device.id } } })
This is not a problem with Dgraph, but with your use of the useMutation return function.
deleteProduct({ filter: { id: device.id } })
Should be
deleteProduct({ variables: { filter: { id: device.id } } })