Primary key 0 for table &1 does not exist on the database

What causes this issue?

No corresponding primary key was found on the database for the DDIC
definition of the table <(>&<)>1.

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?

Check whether this configuration is correct. If it is, the attribute
COMPFLAG must be set correctly in DD02L.
If not, the table <(>&<)>1 must be activated again.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.