PO from SRM to PI to ECC

Hi Experts,

we have an issue in which Purchase Orders are created in SRM system. They are then passed to ECC system via PI system.

I would like to know is there any way we can block/check these Purchase orders as these POs have some incorrect data. I dont know where should i check/debug the issue as there are 3 systems involved.

As per my understanding, I have to block/stop these POs in a queue when they are coming from PI to ECC. and then debug from the queue.

i am not sure if i am correct or if there is any other way of doing it. Can anyone throw more light on the solution.

Thanks

Meenakshi