This hands-on describes how to update the code in NBU and the User firmware using the ISP.
Hi,
This Hands On shows how to identify if the NBU does not match with the CPU code. Could you please take a look and let me know if solves the problem.
FRDM-MXCW71: Hands On 2: Recognize NBU Incompatible Versions - NXP Community
Regards
Daniel