Explanation
To enable automatic generation of the purchase order at the time of goods receipt without a corresponding purchase order, you must meet the following prerequisites:
Automatic purchase order generation is activated for the movement type in Customizing, which means that the system will create a purchase order automatically when you post a goods receipt with movement type 501 (Goods receipt without purchase order).
A default purchase order type is specified for the goods receipt, which determines the document category and number range for the purchase order.
A valid purchasing info record exists for the material and supplier combination, which contains information about the conditions and delivery data for a material from a specific vendor.
References: SAP S/4HANA Sourcing and Procurement | SAP Learning, Course S4510, Unit 2, Lesson
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