Let $X\subset\mathbb{P}(a_0,\dots,a_n)$ and $Y\subset\mathbb{P}(b_0,\dots,b_n)$ be two weighted complete intersections with mild (say terminal) singularities.
Assume that there is an isomorphism $f:X\rightarrow Y$. Under which hypothesis may we conclude that $\mathbb{P}(a_0,\dots,a_n)\cong \mathbb{P}(b_0,\dots,b_n)$ and $f$ is induced by an automorphism of the ambient weighted projective space $\mathbb{P}(a_0,\dots,a_n)$?
I am particularly interested in the case when $X$ is a Fano $3$-fold hypersurface in a $4$-dimensional weighted projective space.