How To Fix DT902 - &-structure: invalid change: data type of field & changed

DT902 - Overview

• Message type: E = Error

• Message class: DT - Table activation (incl. indexes)

• Message number: 902

• Message text: &-structure: invalid change: data type of field & changed

What causes this issue?

For a BAPI or an IDOC structure, you have attempted to change a field
type. The structure, however, is marked as "frozen". This means that, in
this version, it is delivered productive in BAPIs and IDOCs,
respectively. A new delivery with the executed change would contradict
the agreed interface.

System Response

Activation is rejected.

How to fix this error?

Take back the change. If it is absolutely necessary, you will then have
to remove the "frozen" status. For information on how to do this and
what you need to watch out for, refer to Note 1297242.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

DT902 - Details

• The SAP error message DT902, which states "Structure: Invalid change: Data type of field & changed," typically occurs when there is an attempt to modify the data type of a field in a structure that is already being used in various places within the SAP system. This can happen during the development of ABAP programs, enhancements, or when modifying data dictionary objects.
  
  Cause:
  
  Data Type Change: The primary cause of this error is that the data type of a field in a structure is being changed after it has already been defined and used in other objects (like tables, views, or programs).
  Dependencies: SAP structures are often used in multiple places, and changing the data type can lead to inconsistencies or errors in those dependent objects.
  Transport Requests: If the change is being made in a transport request, it may conflict with existing objects that rely on the original data type.
  
  
  Solution:
  
  Avoid Changing Data Types: