Group Price not working in Bundle Products Magento

I am creating Simple and Bundle product programmatically using Magento, However Group Price is working perfectly in Simple Product but its not working when I create Bundle Product any idea why this happening?

If you have any code or if I am missing anything please guide me here is my code.

$groupPrices = array(

        array(
            'website_id' => 1,
            'cust_group' => 8,
            'price' => 10
        ),

        array(
            'website_id' => 1,
            'cust_group' => 6,
            'price' => 15
        )
    );

    $Product->setData('group_price', $groupPrices);

The above code working perfectly in simple product but not working in Bundle Product.

Thanks in advance