CC26xx Wachdog Timer (seRetload function), sync trigger time in sleep(idle or standby) mode

I have used watchdog function and wanted to kick watchdog using a normal timer, every 5 seconds.

The timer of watchdog is set 10 sec by using setReload(). and my device uses power saving .

But the watchdog does not trigger after 10 sec, when a value of ReloadGet() and current value is compared. (refer Log_warning2)

So, i guess that watchdog timer is delayed in sleep mode, because the clock source of MCU is changed 48Mhz to 32Khz .

How can the watchdog be exactly triggered after 10 sec, when a system uses power saving mode.

//in board.c file 

/*
 *  ========================== Watchdog begin =======================================
 *
 */

#include <ti/drivers/Watchdog.h>
#include <ti/drivers/watchdog/WatchdogCC26XX.h>

WatchdogCC26XX_Object watchdogCC26XXObjects[CC2650_WATCHDOGCOUNT];

const WatchdogCC26XX_HWAttrs watchdogCC26XXHwAttrs[] =  {
  {
    .baseAddr = WDT_BASE,
    .intNum   = INT_WATCHDOG,
  }
};

const Watchdog_Config Watchdog_config[] = {
  { &WatchdogCC26XX_fxnTable, &watchdogCC26XXObjects[0], &watchdogCC26XXHwAttrs[0] },
  { NULL, NULL, NULL },
};

/*
 *  ========================== Watchdog end =========================================
*/



//............
//in task.c file 
#include <ti/drivers/Watchdog.h>
#include <ti/drivers/watchdog/WatchdogCC26XX.h>
#include<driverlib/watchdog.h>

Clock_Struct watchdogKickTimer;
Watchdog_Handle hWDT;

void watchdogKickHandler(UArg arg)
{

  Log_warning2("%d, %d", WatchdogReloadGet(), WatchdogValueGet());
  Watchdog_clear(hWDT);
}


//...
void someTask()
{

  Watchdog_Params wp;
  Watchdog_Params_init(&wp);
  wp.callbackFxn    = NULL;
  wp.debugStallMode = Watchdog_DEBUG_STALL_ON;
  wp.resetMode      = Watchdog_RESET_ON;
  hWDT = Watchdog_open(CC2650_WATCHDOG0, &wp);
  Watchdog_setReload(hWDT, 10*1500000); // 10sec (WDT runs always at 48MHz/32)

  Util_constructClock(&watchdogKickTimer, watchdogKickHandler,5*1000, 5*1000, true, NULL) //kick watchdog, every 5 second 
}