https://userapps.support.sap.com/sap/support/knowledge/en/2815721
2815721 - ME51N does not determine Scheduling Agreement as source | SAP Knowledge Base Article
"Source Determination" indicator is ticked in ME51N for triggering the automatic determination of Source of Supply. The scheduling agreement maintained in...
https://finance.duke.edu/resource/creating-purchase-requisition-items-not-material-master-sap-transaction-me51n/
Creating a Purchase Requisition for Items Not in the Material Master - SAP Transaction ME51N |...
This guide provides instructions on creating a purchase requisition for items not in the material master material master using SAP Transaction ME51N.
https://userapps.support.sap.com/sap/support/knowledge/en/1603637
1603637 - How to Use Multiple Purchasing Catalogs in ME51N/ME21N | SAP Knowledge Base Article
You require guidance on how to utilize more than one purchasing catalog in transactions ME21N or ME51N.
https://userapps.support.sap.com/sap/support/knowledge/en/2847121
2847121 - Error KI235 is triggered instead of ME083 in ME21n or ME51n | SAP Knowledge Base Article
You defined a field, for example cost center, as mandatory. You do not fill the value for that field. The expected error is ME083 "Enter Cost Center", but...