Data model &1, entity type &2: Application field is still empty

What causes this issue?

This message is only displayed
in SAP systems
for data models in the SAP namespace
for entity types of storage and usage type 1
where no application is defined
The application is needed for the pricing / license auditing
functionality to assign the counted MDG objects to a corresponding
pricing unit.

System Response

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

How to fix this error?

To define the application per entity type of a data model, execute
report USMD_ENTER_PRICING_DATA. The application (USMD_APPL) corresponds
to the pricing unit. Possible values for your application are defined in
interface IF_EX_USMD_PRICING. If no application is defined, the
corresponding entity is counted as a custom object (which corresponds to
pricing unit '8181').

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.