Message type: E = Error
Message class:  BOS01 - Customer BOS Processing 
Message number: 220
Message text: Supplem. line is not allowed in combination with Conting. or Altern.line
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The SAP error message BOS01220 indicates that there is an issue with the configuration of a supplementary line in a document that is not compatible with contingent or alternative lines. This error typically arises in the context of sales orders, purchase orders, or other document types where line items can be categorized in different ways.
Cause: The error occurs when: A supplementary line item is being added to a document that already contains contingent or alternative line items. The system settings or document configuration do not allow for the combination of these types of line items.
Solution: To resolve this error, you can take the following steps: Review Document Configuration: Check the configuration settings for the document type you are working with. Ensure that the settings allow for the combination of supplementary lines with contingent or alternative lines. Modify Line Items: If the document already contains contingent or alternative lines, consider removing them or changing the type of
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