Two Purchase Requisitions created on MRP for one Sales Order

Hi,

A Sales Order has been created with one schedule line and one delivery date. When MRP is run it creates 2 Purchase Requisitions. The material in the Sales Order is a Prepack Material and has a component attached in the BOM. Please advice as to why the order is splitting when MRP is run and also why 2 PR's are created.

Thank you for your help.