  The objective of the present paper is to prove the non-existence of real
hypersurface with pseudo-parallel normal Jacobi operator in complex two-plane
Grassmannians. As a corollary, we show that there does not exist any real
hypersurface with semi-parallel or recurrent normal Jacobi operator in complex
two-plane Grassmannians. This answers a question considered in [Monatsh Math,
172 (2013), 167-178] in negative.
