MSFS2020 ATR72 Autopilot Won't Engage

In the words of V1 Simulations, the ATR is dead to me.

Despite all my attempts to get the autopilot working, it refuses to connect. I am certain that there's a binding issue but I've not found it.

Thanks to all who commented.

I'm using the CRJ-700 instead for my virtual airline flights.

Best regards,

Peter