Timer Interrupt does not occur

Hello. I took timer project example as reference and wanted to integrate a portion into my project that uses RTOS environment. Now my main file look like this:

void main()
{
	// Board Initialization
	BoardInit();

	// Configure the pinmux settings for the peripherals exercised
	PinMuxConfig();

	// Setup the Leds
	GPIO_IF_LedConfigure(LED1|LED2|LED3);
        GPIO_IF_LedOff(MCU_ALL_LED_IND);

    Timer_IF_Init(PRCM_TIMERA0, g_ulBase, TIMER_CFG_PERIODIC, TIMER_A, 0);
    Timer_IF_IntSetup(g_ulBase, TIMER_A, TimerBaseIntHandler);
    Timer_IF_Start(g_ulBase, TIMER_A, 2000);

	while ( !g_bChoise )
	{
		// Loop here until the ISR occurs
	}
    
    //other code...


}

and the timer interrupt handler is this

void TimerBaseIntHandler(void)
{
    // Clear the timer interrupt.
    Timer_IF_InterruptClear(g_ulBase);

    g_bChoise = TRUE;

    GPIO_IF_LedToggle(MCU_GREEN_LED_GPIO);
}

As you can see i haven't changed anything from the timer example program. My program is simply waiting for the interrupt to occur in main function, and when it does occur it will go beyond that loop. But the problem is the interrupt does not occur. If i go to the other example project it runs just fine, so i suspect that the only possible cause is something with me using OS environment. When i run the program i see the HWI instance of the timer ISR generated in ROV and it says "dispatched", but i also saw it once saying "enabled, pending". But obviously it never triggers. I can't figure out what to do to overcome this issue. Any help will be very appreciated. Thanks in advance.