You're confusing two different notations. There is a long way to describe a permutation and a short way. The long way list which element maps to which:
$$\sigma = \begin{pmatrix} 1 & 2 & 3 & 4 \\\ 1 & 4 & 2 & 3 \\\ \end{pmatrix}$$ Here we have $1$ as a fixed element, while $\sigma(2)=4, \sigma(3)=2$, and $\sigma(4)=3$.
The short way is to write out cycles; the same permutation can be written $$\sigma = (1)(2 4 3)$$ showing that $1$ is fixed, while we have $2 \to 4 \to 3 \to 2$.
In your answer for $\alpha^2$ and $\alpha^2\beta$, you've written out the bottom row of the long notation, which doesn't make sense when read as cycle notation.