How To Fix WL386 - ABAP data type '&V2&' is not allowed in a container operation

WL386 - Overview

• Message type: E = Error

• Message class: WL - Workflow: run-time messages

• Message number: 386

• Message text: ABAP data type '&V2&' is not allowed in a container operation

What causes this issue?

Element or expression &V1& has the ABAP data type '&V2&' which is not
supported.
The following abbreviations are used in the message:

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

'I': whole numbers (ABAP data type: Int1, Int2, Int4)
'P': packed numbers with decimal places and signs (Dec, Packed)
'N': character string with numerical values (Numc)
'C': character strings (Character)
'D': date
'T': time
'O' or 'o': objects from the Business Object Repository

System Response

The compare or calculate operation is not accepted in this form. The
workflow definition contains errors.

How to fix this error?

Arithmetic operations or assignments can only consist of elements or
values based on one of the following data types:
integers (internal ABAP data type I or X)
packed numbers, with decimal places if applicable (ABAP data type)
numeric character strings (ABAP data type N)
character strings (ABAP data type C)
date (ABAP data type D)
time (ABAP data type T)
objects from the Business Object Repository (Workflow)
Floating-point numbers (type F) are not permitted. You should therefore
only select elements or values with the types listed above.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message WL386 - ABAP data type '&V2&' is not allowed in a container operation ?

  The SAP error message WL386 indicates that there is an issue with the ABAP data type being used in a container operation. Specifically, it states that the data type represented by &V2& is not allowed in the context of the operation being performed. This typically occurs when you are trying to use a data type that is incompatible with the expected types for a container operation, such as a table or a structure.
  
  Cause:
  
  Incompatible Data Type: The data type you are trying to use in a container operation (like a table, internal table, or structure) is not supported. For example, certain complex types or user-defined types may not be allowed.
  Incorrect Declaration: The variable may not be declared correctly or may not be initialized properly before being used in the container operation.
  Contextual Misuse: The operation you are trying to perform may not be valid for the data type you are using. For