How To Fix /IWBEP/CM_V4_MED389 - Nullable collection not allowed in property '&1'

/IWBEP/CM_V4_MED389 - Overview

• Message type: E = Error

• Message class: /IWBEP/CM_V4_MED -

• Message number: 389

• Message text: Nullable collection not allowed in property '&1'

Self-Explanatory Message

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/IWBEP/CM_V4_MED389 - Details

• The SAP error message /IWBEP/CM_V4_MED389 Nullable collection not allowed in property '&1' typically occurs in the context of OData services when there is an issue with the definition of a collection property in your OData model. This error indicates that a collection property is defined as nullable, which is not allowed in the context of the OData service.
  
  Cause:
  
  Nullable Collection Definition: The error arises when a collection property (an array or list of items) is defined in the OData model as nullable. In OData, collections cannot be nullable; they must always be present, even if they are empty.
  Model Configuration: The issue may stem from the way the OData model is configured in the backend, particularly in the metadata definition of the entity type.
  
  
  Solution:
  To resolve this error, you need to ensure that the collection property is defined correctly in your OData model. Here are the steps to fix the issue:
  
  
  Check the Entity