MSP430G2553: Watch dog program not working

#include "msp430g2553.h"
unsigned int Timer1ms=0;
unsigned int count=0;
unsigned int temp=0;
void Timer_Init();
void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;// Stop the WDT to prevent reset                // Count value for delay
  Timer_Init(); // Initialize timer
  WDTCTL = WDT_ARST_1000;  // 1 sec watchdog interval
  count=0;
  temp=0;//flag
  while(1)
  {
      count++;
      if(count>5000)
      {
          temp=1;// after 5000 count temp will set 
          count=0;//clearing count
      }

  }
}

void Timer_Init()
{
    DCOCTL = CALDCO_8MHZ;
    BCSCTL1 = CALBC1_8MHZ;
    TA0CCTL0=CCIE;
    TA0CTL=TASSEL_2+MC_1+ID_3;//SMCLK, Up mode, Divider -->1
    TA0CCR0=999;//from above calculation
    _BIS_SR(GIE);//off CPU until interrupt occurs
}

#pragma vector=TIMER0_A0_VECTOR
__interrupt void TIMER0_A0_ISR(void)
{
    
   
     if(temp==0)// the WDT count clears every 200ms if temp is 0 else WDT won't clear itself, so WDT resets the controller
    {
        Timer1ms++;
        if(Timer1ms>=200)
        {
            WDTCTL = WDTPW + WDTCNTCL;// Clear WDT counter
            WDTCTL =  WDT_ARST_1000;  //again 1sec
            Timer1ms=0;
        }
    }
}