RTC_C interrupt genration issue

Dear sir,

pl. find below code, we are finding problem in genrating interrupt in RTC_C and pls suggest some solution. I m using controller MSp430F6736.

#include "msp430f6736.h"
#include <in430.h>
#include <math.h>

int count = 0;
void main(void)
{ 
 WDTCTL = WDTPW | WDTHOLD;

 RTCCTL0_H  =    RTCKEY_H;                      //unlock RTC = 0xA5
    RTCCTL0_L |= RTCRDYIE | RTCTEVIE | RTCOFIE;                              //Enable RTC ready interrupt
    RTCCTL1 |= RTCMODE | RTCHOLD | RTCBCD | RTCSSEL_3;// | RTCTEV_0;                        //RTCRDY, RTC in calendar Mode ,hold RTC before WRITTING any value
 

    RTCDAY = 0X05;
    RTCMON = 0x06;
    RTCYEAR = 0x2015;
    RTCSEC = 0x00;

   RTCCTL1 &= ~RTCHOLD;        // start RTC
 RTCCTL0_L |= RTCRDYIE | RTCTEVIE;                              //Enable RTC ready interrupt
    __bis_SR_register(LPM3_bits | GIE);     // Enter LPM3 w/ interrupts

}

#pragma vector=RTC_VECTOR
__interrupt void RTCISR(void)
{
 count++;
 switch(__even_in_range( RTCIV, 16))
    {
     case RTCIV_RTCRDYIFG:
     {
   while(!(RTCCTL1 & RTCRDY))
   {
    sec = RTCSEC;
      }
        break;
     }
     case RTCIV_RTCTEVIFG :
     {
      __no_operation();
     }
     break;
     case RTCIV_RTCAIFG:                  // RTCAIFG
      __no_operation();                   // Interrupts every alarm event
      break;
      case RTCIV_RT0PSIFG:                // RT0PSIFG
      break;
      case RTCIV_RT1PSIFG:                // RT1PSIFG
      break;
      case 14: break;                     // Reserved
      case 16: break;                     // Reserved
      default: break;
    }
}