  It has been recently suggested the existence of a neutral bound state of two
neutrons and a $\Lambda$ hyperon, $^3_\Lambda n$. We point out that using
either simple separable potentials or a full-fledged calculation with realistic
baryon-baryon interactions derived from the constituent quark cluster model
there is no possibility for the existence of such a $\Lambda nn$ bound state.
For this purpose, we performed a full Faddeev calculation of the $\Lambda nn$
system in the $(I,J^P)=(1,1/2^+)$ channel using the interactions derived from
the constituent quark cluster model which describe well the two-body $NN$ and
$NY$ data and the $\Lambda np$ hypertriton.
