cc2541 unexpectedly stop advertising while no connection is made

I'm using CC2541 with CC2591, and ble stack is 1.4.0.

it's stop advertising after using my board a while (it happened when keep using like 1 hours or 12 hours ) and found that sniffer and mobile could not scan the CC2541.
When CC2541 stop advertising , I took debugger tool to check gapRoleState and it was GAPROLE_ADVERTISING.

At the same time , I can blink LED by long press the button(by osal timer, i think it says the system is still working).
After all , only reset or restart helps it back to work on advertising.

Here’s the code about advertising…, and LED blinking

#define DEFAULT_ADVERTISING_INTERVAL_MIN          32  // 20ms
#define DEFAULT_ADVERTISING_INTERVAL_MAX          48  // 30ms
#define DEFAULT_DISCOVERABLE_MODE             GAP_ADTYPE_FLAGS_GENERAL

{
    // For other hardware platforms, device starts advertising upon initialization
    uint8 initial_advertising_enable = TRUE;

    // By setting this to zero, the device will go into the waiting state after
    // being discoverable for 30.72 second, and will not being advertising again
    // until the enabler is set back to TRUE
    uint16 gapRole_AdvertOffTime = 0;
}

  // Set advertising interval
  {
    uint16 advIntMin = DEFAULT_ADVERTISING_INTERVAL_MIN;
    uint16 advIntMax = DEFAULT_ADVERTISING_INTERVAL_MAX;

    // GAP_SetParamValue( TGAP_LIM_DISC_ADV_INT_MIN, advInt );
    // GAP_SetParamValue( TGAP_LIM_DISC_ADV_INT_MAX, advInt );
    GAP_SetParamValue( TGAP_GEN_DISC_ADV_INT_MIN, advIntMin );
    GAP_SetParamValue( TGAP_GEN_DISC_ADV_INT_MAX, advIntMax );
  }

Init I/O
{
    // Default State of I/O are output and low
    P0SEL = 0; // Configure Port 0 as GPIO
    P1SEL = 0; // Configure Port 1 as GPIO
    P2SEL = 0; // Configure Port 2 as GPIO
    
    P0DIR = 0xFE; // Port 0 pins P0.0 as input (buttons), others as output
    P1DIR = 0xF3; // All port 1 pins (P1.0-P1.7) as output
    P2DIR = 0x1F; // All port 1 pins (P2.0-P2.4) as output

    P0 = 0;    // All pins on port 0 to low
    P1 = 0;    // All pins on port 1 to low
    P2 = 0;    // All pins on port 2 to low
}

// Enable PA/LNA
{
    HCI_EXT_SetTxPowerCmd(HCI_EXT_TX_POWER_0_DBM);
    HCI_EXT_SetRxGainCmd(HCI_EXT_RX_GAIN_HIGH);
    HCI_EXT_ExtendRfRangeCmd();
}

// ...

uint16 SimpleBLEPeripheral_ProcessEvent( uint8 task_id, uint16 events )
{
  // ...

  if ( events & LED_BLINKING_EVT )
  {
    LED_PIN = ~LED_PIN;                // 切換LED狀態
    
    counter_led++;
    if ( counter_led < led_blink_times )
    { // restart led blinking timer
      osal_start_timerEx( simpleBLEPeripheral_TaskID, LED_BLINKING_EVT, LED_BLINKING_PERIOD );
    }
    return (events ^ LED_BLINKING_EVT);
  }
}

I'm looking for the answer why it stop advertising.