Message type: E = Error
Message class:  SEPMRA_PRODUCT - EPM Fiori Ref Apps: Message Class for Product 
Message number: 124
Message text: Sub-category &1 does not belong to category &2
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
Unfortunately, there isn't any extra information in this error notice.
First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).
Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.
You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.
The SAP error message SEPMRA_PRODUCT124 indicates that there is a mismatch between the sub-category and the category assigned to a product in the SAP system. This error typically occurs in the context of product management, particularly when dealing with product hierarchies or classifications in SAP's Product Lifecycle Management (PLM) or similar modules.
Cause: The error arises when: A sub-category is assigned to a product that does not belong to the specified category. There may be a configuration issue in the product categorization settings. The product data might have been incorrectly entered or modified, leading to inconsistencies in the category-sub-category relationship.
Solution: To resolve this error, you can follow these steps: Check Product Configuration: Navigate to the product master data in the SAP system. Verify the category and sub-category assignments for the affected product. Correct Category-Sub-category Assignment: Ensure that the sub-category assigned to the product is valid for the specified category. If necessary, change the sub-category to one that is valid for the category
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
SEPMRA_PRODUCT123 Sub-category &1 does not exist
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
SEPMRA_PRODUCT122 The product must be assigned to a sub-category
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
SEPMRA_PRODUCT130 Specify a currency
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
SEPMRA_PRODUCT131 Currency &1 does not exist
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
Click on this link to search all SAP messages.