I learned that the selection rules for electric dipole transition in a hydrogen-like atom is

\begin{align} \delta l & = \pm1 \\ \delta j & =0,\pm1 \\ \delta m_j & =0,\pm1 \end{align}

I then came across a diagram that says it marked all transitions consistent with electric dipole selection rules for the $2P_{3/2}$, $2P_{1/2},2S_{1/2},1S_{1/2}$ hydrogen states:

Why is the $2P_{3/2}$ to $2S_{1/2}$ transition not possible since it satisfies the all the selection rules?