VocALign does not have a realtime version in Pro Tools, and so does not show up in the mixer inserts at all.
Instead, please find it in one of the two following places depending on your Pro Tools and VocAlign versions:
1) With any VocAlign version, the AudioSuite menu found at the top of your screen.
If your plug-ins are being sorted by category, VocAlign will be found under the Other submenu:
2) In Pro Tools 2024.6 and above, with VocAlign 6 Pro or Standard,
as an ARA effect added from the right-click menu, or the Clip menu.