@chenyin_h
Thank you for your reply.
At the very beginning, I used hardware: the RDB2 board, and the software was as shown in Figure 1. It ran without any abnormalities on the S32DS3.5, and there was no abnormality in the operation when the connection to the opposite CAN device was disconnected.

Figure 1
Later, when the software was modified to run on VxWorks and the hardware was a custom motherboard, there was a problem where the opposite device disconnected. After the firmware detected the error, it would continuously report notifications (ackerr). Eventually, the software ended abnormally.
I attempted to look for a solution to similar problems in the provided sample project Can_Llce_DS_Loopback_S32G274A_M7, but found that the project did not have a specific solution for the ackerr issue. It seemed that only a stub function was written, leaving an interface for the upper layer to notify of errors.

Figure 2
I would like to know how the ACK exception is handled on LLCE1_0_9. This way, I can refer to it to see if the same solution can be applied to my VxWorks system as well.