stock issue in gATP

Hi Experts,

I have a stock in ecc 99,882 for the material X and plant Y. The same stock (99,882) is available in APO for the product X and location Y.

The system is confirming the sales order even if I enter the quantity more than the available stock in APO (99,882).

The sales order is confirming even I enter 10 lakhs qty for the item in the SO (it is greater than than the available stock which is available in the APO/ECC)

Can you please help me what could be the wrong in this. Why system is confirming the sales order for whatever figure i enter.

Please help

Thanks,