Lua Script CAN Errors

I’m trying to run the basic Lua script example for CAN read (the one found here: here, but I keep getting the following errors in the messages on mission planner:

2/22/2022 8:16:38 PM :  a nil value (global 'CAN')
2/22/2022 8:16:38 PM : Lua: /APM/scripts/CAN_read.lua:4: attempt to index

I have CAN enabled, with CAN_P1_DRIVER set to 1, and CAN_D1_PROTOCOL set to 10.
Is my problem with something with the Lua script or the device I am using to send CAN to the flight controller?