This is the first thread Google returns when searching for "Vertical camera failure" for the Anafi, so I'll just post my findings here.
I had the same problem as everyone else; after updating firmware on the drone, I get a "Vertical camera error" message and the drone no longer responds to commands.
Long story short, at least in my particular case, it seems to be a manufacturing defect with the vertical camera connector to the motherboard, in that it can move to the side and the pins no longer line up. I initially though it was from a recent crash I had with the drone, but looking at the connector with a microscope I see no deformity in either the connector itself or the slot on the motherboard, which is why I suspect this to be a manufacturing defect, where the tolerances are off and the connector can move out of its place.
You can bend the metal bit which is holding the connector in place, to try and lift it up and re-position it. But even if you manage to insert it correctly, it requires very little force to push it out of its correct place. So what I've done is that I've glued it into place, and so far I haven't had any issues with it.
I've given a reference image as to how the connector can move about. From my reference image, the connect can slide leftwards, meaning you have to push it rightwards to move into place. If you look from the bottom very carefully, you can see if the pins are aligned or not.
Considering that this is likely a manufacturing defect and can't be solved through software, if its still under warranty, your best option is to have it replaced.