  In the present work, considering the conservation of isospin in the strong
decays, we investigate the strong decays of the pentaquark molecule candidate
$P_c(4312)$ and its possible higher isospin cousin $P_c(4330)$ in the framework
of the QCD sum rules. What's more, the pole residue of the $\Delta$ baryon with
isospin eigenstate $|II_3\rangle=|\frac{3}{2}\frac{1}{2}\rangle$ is obtained.
If the possible pentaquark molecule candidate $P_c(4330)$ could be testified in
the future experiment, it would shed light on interpretations of the $P_c$
states.
