MODBUS_TCP RTOS Task

void setup() {
  Serial.begin(9600);        // Open serial communications and wait for port to open
  delay(500);
 
  Ethernet.init(5);                                            // SS pin
  Ethernet.begin(mac, ip, SubnetMask );    // start the Ethernet connection
  //Ethernet.begin(mac, ip );                            // start the Ethernet connection
 
  delay(500);                                                // give the Ethernet shield a second to initialize
  modbus_TCP_init_val();
  mb.server(502);                                        // Listen TCP server 
    

/////////////////////////////////////////////////////////////////////////////////////////////////////////////
///////////////////////////////////// MODBUS TCP TASK ///////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////////////

   xTaskCreatePinnedToCore(
    Task_MODBUS_TCP_Service
    ,  "Task_MODBUS_TCP_Service"
    ,  8192                              // Stack size
    ,  NULL                             // When no parameter is used, simply pass NULL
    ,  0                                   // Priority
    ,  &Task_mb_tcp_hdlr            // With task handle we will be able to manipulate with this task.
    ,  RUNNING_CORE_1        // Core 1 on which the task will run // pin task to core X   
    );
 delay(500);
}

void loop() {
//  [B]mb.task();                  // working when unmark comment ![/B]
}

void Task_MODBUS_TCP_Service(void *pvParameters){  // This is a task.
  (void) pvParameters;     
   while(1){                                      // A Task shall never return or exit. 
    [B]mb.task();                                 // when is located here - not working ! [/B]
   vTaskDelay(pdMS_TO_TICKS(1));
  }
            
 }