Message type: E = Error
Message class:  MDG_BS_MAT_SI - Message Class : Material Replication Services Implementation 
Message number: 021
Message text: A description is already maintained for language &1
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The SAP error message MDG_BS_MAT_SI021 indicates that there is an attempt to create or update a material description in a specific language, but a description for that language already exists in the system. This error typically occurs in the context of Material Master Data Governance (MDG) when you are trying to maintain descriptions for materials.
Cause: The primary cause of this error is that the system has detected that a description for the material in the specified language (denoted by &1 in the error message) is already present in the database. This can happen if: You are trying to create a new material with a description in a language that already has an existing description. You are trying to update a material's description in a language where a description already exists.
Solution: To resolve this error, you can take the following steps: Check Existing Descriptions: Navigate to the Material Master data in SAP and check if a description
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