  Recently, Belle II reported on the first measurement of $\mathcal{B}(B^\pm\to
K^\pm \nu\bar{\nu})$ which appears to be almost $3\sigma$ larger than predicted
in the Standard Model. We point out the important correlation with
$\mathcal{B}(B\to K^{\ast} \nu\bar{\nu})$ so that the measurement of that decay
mode could help restraining the possible options for building the model of New
Physics. We then try to interpret this new experimental result in terms of
physics beyond the Standard Model by using SMEFT and find that a scenario with
coupling only to $\tau$ can accommodate the current experimental constraints
but fails in getting a desired $R_{D^{(\ast )}}^\mathrm{exp}/R_{D^{(\ast
)}}^\mathrm{SM}$, unless one turns the other SMEFT operators that are not
related to $b\to s\ell\ell$ or/and $b\to s\nu\nu$.
