Purchase Order Number is not showing in Supplier Line Item report.
The field Purchase Order Number cannot appear on the Supplier Line item as the Purchase Order is not part of the Vendor/Supplier Line item. The Purchase Order Number will not be copied to Supplier Line item automatically as this may not be unique in the process.
A cloud substitution can be created (see KBA: FAQ: Validation and Substitution Cloud BAdIs Availability) using BAdI FIN_ACDOC_SUBSTITUTION.
Than the substitution of the allocation number directly for the Supplier Item will be possible.
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