Message type: E = Error
Message class:  SLS_PAYSP - Payment Service Provider Integration 
Message number: 026
Message text: New pricing not permitted in doc. &1; payment by payment service provider
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The SAP error message SLS_PAYSP026 indicates that there is an issue with the pricing in a document when attempting to process a payment through a payment service provider (PSP). This error typically arises in scenarios where the pricing conditions have changed or are not allowed to be modified after a certain point in the transaction process.
Cause: Pricing Conditions Changed: The pricing conditions for the document have been altered after the document was created, which is not permitted in the context of the payment processing. Document Status: The document may be in a status that does not allow for changes to pricing (e.g., already processed or completed). Configuration Settings: There may be specific configuration settings in the SAP system that restrict changes to pricing once a payment is initiated or processed through a PSP.
Solution: Review Document: Check the document referenced in the error message (indicated by &1) to see if the pricing conditions have been
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