TM4C1294NCPDT: Timer doesn't work as expected

I have configured the Timer0 as 64 bit and working in periodic mode. However, the results look like I can only configure the time for the first time to enter the TimerA_IntHandler function. After that, I cannot control the time to enter the TimerA_IntHandler at all. It is always entered the interruption as fast as possible. I wonder if there is any actions which need to be done in the TimerA_IntHandler function so the periodic mode can be continued? Or did I do something wrong in the timer configuration? Thanks. 

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// Configure the Timer.

void ConfigureTimer(void){

     //=================  timer 0 config  64-bit timers =================

         SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER0);

         // Configure the  64-bit periodic timers

         TimerConfigure(TIMER0_BASE, TIMER_CFG_PERIODIC);

        // Setup the interrupts for the timer timeout.

        TimerIntEnable(TIMER0_BASE, TIMER_TIMA_TIMEOUT);

        TimerIntRegister(TIMER0_BASE, TIMER_A,TimerA_IntHandler);

        TimerEnable(TIMER0_BASE, TIMER_A);

        TimerLoadSet64(TIMER0_BASE, 100000000); // x SEC

}

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