Order of subgroup of symmetric group $S_n$

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$H=\{\sigma \in S_n :\sigma(3)=3\}$

where $S_n$ is the symmetric group of degree $n$. We need to find the order of the subgroup $H$. My book has the answer 2.

But my intuition says that by fixing $3$, we can permute the rest of the $n-1$ symbols, thus we should have $(n-1)!$ as the order of $H$.

Is that the correct way to think?