Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 301
Message text: Housebank ID missing for source house bank acct ID &1
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 CNV_20200_CHECK301 indicates that there is a missing House Bank ID for a specified source house bank account ID. This error typically arises during data migration or conversion processes, particularly when using SAP's Conversion Tools or during the implementation of SAP S/4HANA.
Cause: The error occurs when the system is unable to find a corresponding House Bank ID for the specified source house bank account ID. This can happen due to several reasons: Data Inconsistency: The source data may not have been properly mapped to the target system, leading to missing or incorrect entries.
Configuration Issues: The House Bank configuration in the target system may not be set up correctly, or the necessary entries may not exist. Migration Errors: During the data migration process, some records may have been skipped or not migrated correctly.
Solution: To resolve this error, you can follow these steps: Check House Bank Configuration: Go to the transaction code FI12 (House Bank)
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
CNV_20200_CHECK300 Securities account group merge into target &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...
CNV_20200_CHECK299 Merge into (CoCd &1, house bank &2, Acct ID &3)
What causes this issue?  Merge into (company code &V1&, house bank &V2&, account ID &V3&).System Response  WarningHow to fix t...
CNV_20200_CHECK302 Securities account merge into target &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...
CNV_20200_CHECK303 No splits of cash journal business transactions
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.