Message type: E = Error
Message class:  FINS_FI_DEFSUM - Deferred Summarization 
Message number: 021
Message text: & line items would be deleted from ACDOCA and inserted into ACDOCD.
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 FINS_FI_DEFSUM021 typically relates to issues with the financial document processing in the Universal Journal (ACDOCA) and the related tables in SAP S/4HANA. This error can occur during the execution of certain financial transactions or during the posting of documents, particularly when there are inconsistencies or issues with the data being processed.
Cause: Data Inconsistency: The error may arise due to inconsistencies in the data between the ACDOCA (Universal Journal) and ACDOCD (Document Segment) tables. This can happen if there are issues with the document splitting or if the data does not meet the required criteria for posting. Document Splitting Configuration: If the document splitting is not configured correctly, it can lead to errors when trying to post documents that require splitting. Missing or Incorrect Data: If required fields are missing or if there are incorrect values in the line items, it can trigger this error. Custom Code or Enhancements: If there
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
FINS_FI_DEFSUM020 & balance entries would be inserted into ACDOCA and ACDOCD.
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FINS_FI_DEFSUM012 Internal Error: Number of inserted and deleted line items differ (&1, &2)
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FINS_FI_DEFSUM022 & balance entries were inserted into ACDOCA.
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FINS_FI_DEFSUM023 & balance entries were inserted into ACDOCD (Details).
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.