rpcUnified hangs when calling rpc_system_version()

sure:

#include “seeed_rpcUnified.h”

void setup()
{
Serial.begin(115200);
while (!Serial)
{
};

delay(5000);

Serial.printf("start\n");
Serial.print("rpc_system_version= ");
String theVersion = rpc_system_version();
Serial.println(theVersion);

}

void loop()
{
}