Message type: E = Error
Message class:  UPGBA_IMPANA - Messages used by Upgrade Impact Analysis 
Message number: 402
Message text: &1 cannot be changed on &2 due to read-only restriction on &3
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 UPGBA_IMPANA402 indicates that a specific field (denoted as &1) cannot be changed on a particular object (denoted as &2) due to a read-only restriction on another object (denoted as &3). This typically occurs during data migration or system upgrades when certain fields are locked or restricted from being modified.
Cause: Read-Only Restrictions: The field you are trying to change is set to read-only due to system settings, configuration, or the current state of the object. Data Migration: During data migration processes, certain fields may be locked to prevent inconsistencies or data integrity issues. Authorization Issues: The user may not have the necessary permissions to modify the field in question. System Configuration: The system may be configured to restrict changes to certain fields based on business rules or workflows.
Solution: Check Field Status: Verify the status of the field you are trying to change. Ensure that it is not set to read-only in the
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
UPGBA_IMPANA401 &1 will not work on &2 due to read-only restriction on &3
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
UPGBA_IMPANA400 Read-only restriction on &1 is considered uncritical
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
TPM_TRL060 No update types are maintained for position management procedure &1
What causes this issue?  In the Customizing activity "Assign Update Types for Derived Business Transactions", no update types are entered fo...
TPM_TRL061 Update type is not assigned (see long text)
What causes this issue?  In the Customizing activity <DS:SIMG.TRLV_DFT_ASSGN> Assign Update Types for Derived Business Transactions</> , n...
Click on this link to search all SAP messages.