Topological protection of singularities for the non-Hermitian problem is one of the recent focuses in condensed matter physics. Exceptional points and rings with symmetry constraints are typical examples. In this respect, the effects of interaction may destroy the structures and modify the conclusions for free fermion systems. We have analyzed the problem and demonstrated it in concrete models in our recent paper, “Fate of exceptional points under interactions: Reduction of topological classifications” by Tsuneya Yoshida and Yasuhiro Hatsugai, which has been published in Physical Review B (Feb.8, 2023). See also arXiv:2211.08895.