Hi @dParker_22 ,
Your issues should still in the code side, when you use the RT1020 SDK flexCAN project directly, you didn't meet the issues, right?
Just when you add the flexcan drivers, then meet issues, you can check your definition, and compare with the SDK code:
SDK_2_10_0_EVK-MIMXRT1020\boards\evkmimxrt1020\driver_examples\flexcan
make sure your code write is correct at first.
If you still have issues, just kindly let me know.
Best Regards,
Kerry