Probably the ECU is sending the Ethernet frames on a port that is not defined in CANoe as belonging to higher protocol level and is therefore not interpreted accordingly.
This configuration aspect can be adapted using CANoe option like following:
You can recognize on the small icon in trace if a frame is interpreted or not. It is possible to see all Ethernet events received before their interpretation by setting the following filter:
The destination port of a frame can be read using the detailed view: