PO quantity exceeds PR quantity

Hello

Currently our system allows to create many Purchase Orders referring to the same Purchase Requisition using the App Create Purchase Order - Advanced.

For example, if we have a PR with 5 units of a material we can create two PO with 5 units each one referred to the same PR, having ordered a total of 10 units even though the initial requisition was 5 units.

I would like to know how to prevent this from happening, if a PO is already made with the total units from the PR referred, the system should not allow to make another PO refering to the same PR and exceeding its quantity.

Thank you in advance for your answer.