  Inspired by the work of A. Bonami and S. Poornima that a non-constant
function which is homogeneous of degree $0$ cannot be a Fourier multiplier on
homogeneous Sobolev spaces, we establish analogous results for Fourier
multipliers on the Heisenberg group $ \mathbb{H}^n $ and Weyl multipliers on $
\mathbb{C}^n $ acting on Sobolev Spaces.
