Error when filling the generator table with object &1

What causes this issue?

You tried to create a class &1 object. However, the technical
attributes necessary for creation as a DDIC object are not available.

System Response

Further processing of the DDIC objects had to be therefore cancelled.

How to fix this error?

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

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.