C2000 CAN Transmit Block conflict with External Mode(XCP on CAN)

I'm using the C2000 Microcontroller Blockset for a TI F28379D project, with External Mode (XCP on CAN) enabled for model tuning and signal logging. This setup works perfectly with Vector VN1610 as the CAN-USB device.

However, when I add a C28x CAN Transmit block to the model (with all other settings kept unchanged, and CAN Transmit Block using same can chn with the external mode settings), the ECU is unable to send any CAN messages to the bus. As a result, both the CAN transmit function and External Mode cease to work: no CAN frames are transmitted, the External Mode connection to the board is lost, no CAN traffic is detected on the bus via another CAN-USB device, and Simulink can no longer interact with the ECU in External Mode.

The same issue recurs with the example model "c28x_xcp_can_ext.slx" as in the figure below.

Did I overlook any configuration settings? Or is it possible that using External Mode and the CAN Transmit block simultaneously is not supported? Thank you for reading, and I look forward to your reply.

Figure1-Cannot settup XCP connection.

Figure2-Setting of CAN Transmit Block.

Figure3-Model Settings about CANB and External Mode.