Hi @chenyh
You can try reading bit BOFFREC from the CTRL1 register to confirm if bus off recovery is disabled.
Julin_AragnM_0-1743180977022.png
You can also monitor FlexCAN_Ip_MainFunctionBusOff_Privileged function, since it is in charge of clearing the BusOff Status Flag.
Julin_AragnM_1-1743181053875.png
Best regards,
Julián