  We construct a family of $(2,n)$-almost Grassmannian structures of regularity
$C^1$, each admitting a one-parameter group of strongly essential
automorphisms, and each not flat on any neighborhood of the higher-order fixed
point. This shows that Theorem 1.3 of [9] does not hold assuming only $C^1$
regularity of the structure (see also [2, Prop 3.5]).
