If you are not getting any calls, try doing this:
Go to your BI main settings, and go to the AI tab:
Make sure your IP and port are correct. Then click on the AI Dashboard link to the right of that to confirm you can reach it.
Next, click on the 3 dots next to the "Use custom models" and see if you see something like this:
I think only license-plate is needed, but I had to select all of them.
Uncheck "use custom models". Now click ok and do a test. If you don't see CPAI request count increase, it's because something thinks there is no plate, and doesn't make an OCR request.
I might be 100% wrong, but I just got this working after a few hours of trial and error. I wanted to configure it so I can just change the IP of which CPAI to use w/o changing any camera settings, etc and the above worked for me.