Include TMCWWTOP is empty (see long text)

What causes this issue?

No selection variants were created.

How to fix this error?

Check whether key figure categories are defined in the Customizing for
the allocation rule. If no key figure categories are defined, define
key figure categories according to your requirements.
If key figure categories exist, call report RWSVZUKT to create
selection variants and to generate include TMCWWTOP.

Error message extract from SAP system. Copyright SAP SE.