  In our article [15] description in terms of abstract boundary conditions of
all $m$-accretive extensions and their resolvents of a closed densely defined
sectorial operator $S$ have been obtained. In particular, if
$\{\mathcal{H},\Gamma\}$ is a boundary pair of $S$, then there is a bijective
correspondence between all $m$-accretive extensions $\tilde{S}$ of $S$ and all
pairs $\langle \mathbf{Z},X\rangle$, where $\mathbf{Z}$ is a $m$-accretive
linear relation in $\mathcal{H}$ and
$X:\mathrm{dom}(\mathbf{Z})\to\overline{\mathrm{ran}(S_{F})}$ is a linear
operator such that: \[
\|Xe\|^2\leqslant\mathrm{Re}(\mathbf{Z}(e),e)_{\mathcal{H}}\quad\forall
e\in\mathrm{dom}(\mathbf{Z}). \] As is well known the operator $S$ admits at
least one $m$-sectorial extension, the Friedrichs extension. In this paper,
assuming that $S$ has non-unique $m$-sectorial extension, we established
additional conditions on a pair $\langle \mathbf{Z},X\rangle$ guaranteeing that
corresponding $\tilde{S}$ is $m$-sectorial extension of $S$. As an application,
all $m$-sectorial extensions of a nonnegative symmetric operator in a planar
model of two point interactions are described.
