The default trace topic is not equal to broker system trace topic

The c++ sdk's default trace topic was set to "rmq_sys_TRACE_DATA_DEFAULT_REGION"，and the broker's default trace topic is "RMQ_SYS_TRACE_TOPIC".
Because of above setting，when I switched trace on，causing an exception as follows:
Moreover，the trace topic "rmq_sys_TRACE_DATA_DEFAULT_REGION" is started with "rmq_sys_"，which is regarded as a system topic，and I can't create this topic either.

I want to know if I used trace message in a wrong way.