Reference characteristic &1 at material &2 has unusable field name: &3

What causes this issue?

In the configuration model, a reference characteristic exists with
reference to a field which is not supported in any integration scenario.
In particular: In structure SDCOM, only field VKOND and the fields of
the substructures SDCOM_USR and SDCOM_IS are supported. In structure
MMCOM, only field VKOND is supported.

System Response

In the integration scenario (for example, in a sales order), values of
this reference characteristic are not processed.
Exceptions, where such reference characteristic can be useful, are: a)
user-defined scenarios; b) reference characteristics which are defined
only to use the format and the input help from the data dictionary.

How to fix this error?

Check the configuration model.

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.